Effects of bottom electrode materials (Al, Cu, Ti, and Mo), included in film bulk acoustic resonators (FBARs), on the orientation of piezoelectric AlN thin films and the frequency response characteristic of resonators were investigated. The texture coefficient (TC) for (002) orientation, crystallite size, full width half maximum (FWHM), and surface roughness of deposited AlN films were measured for the various bottom electrodes. The return tosses estimated from the frequency responses of fabricated resonators were also compared. Experimental results showed that the difference of lattice constant and thermal expansion coefficient between the bottom electrode and the AlN film were the most important factors for achieving a high performance resonator.

금속유도 측면 결정화 (Metal Induced Lateral Crystallization; MILC)를 통하여 형성한 다결정 실리콘 박막에 엑시머 (excimer) 레이저를 조사하여 우수한 특성을 갖는 박막 트랜지스터를 제작하였다. MILC 공정 중에 형성되는 금속 유도 결정화 (Metal Induced Crystallization; MIC) 실리콘 박막은 다량의 Ni을 함유하고 있기 때문에, 이에 인접한 MILC 실리콘 박막 내에는 니켈 농도의 점진적인 차이가 발생한다. MILC 다결정 실리콘 박막 내의 Ni 농도 차이는 실리콘 박막의 용융점 차이를 유발하여 레이저 결정화 시에 매우 큰 실리콘 결정립의 성장을 유도한다. 새로운 다결정 실리콘 박막 트랜지스터는 기존의 레이저 결정화 방식으로 제작한 다결정 실리콘 박막 트랜지스터에 비하여 40% 향상된 전계효과 이동도를 나타내었다.

Environmental impact of human activities has become a great concern in most of the countries world-wide, and for years. It has recently focused on potential climate changes due to the increase of green house gases content in the atmosphere. One of these gases is $SF_6$, which is an essential material in electrical applications having excellent dielectric and arc-quenching properties. Though the actual contribution of $SF_6$ to global warming is negligible at present, the control of $SF_6$ emissions seems to be nevertheless imperative. Actually, it is listed in the Kyoto protocol that emissions should not only be duly reported but also the electrical industry which is now the major user of this gas must be able to show that it is possible to use this gas and at the same time preserve the environment. For the development of environmentally-benign electric power equipment and systems, novel gases or gas mixtures are strongly required as the alternatives of $SF_6$ gas. Until now, most research work is focused on the $SF_6/N_2$ mixed gas which is suitable for application in the electrical apparatus with slightly non-uniform fields. Recently, $SF_6/CO_2$ mixed gas also is expected to be promising as a $SF_6$ alternative, especially in highly non-uniform fields and in a gas-impregnated film insulation system. Including these results, the author reviews the research trend or reducing the environmental impact of $SF_6$ gas in this paper.

BiPbSrCaCuO계 초전도 소결체에 산화은을 첨가하여 자기 부양 효과를 나타나는 시료의 제작 조건을 조사하였다. 2%의 산화은이 첨가된 시편에서 자기 부양 효과가 가장 효과적으로 관측되었다. toroidal자석에서 관측되는 자기 부양 효과는 자석의 중심부분에서만 발생하며, 자석의 ring부분에서는 관측되지 않았다. 이 결과는 본 연구의 자기 부양 효과의 발생에는 자석의 형상 및 자속의 분포 형태와 밀접한 관련성이 있음을 의미한다. 자기 부양 효과에 관한 측정 결과로부터 자속 밀도가 극소가 되는 장소에 초전도체가 놓이게 되면 초전도체는 반자성효과로 인하여 초전도체의 상하로부터 작용하는 자기력을 받게 된다. 또한 산화은을 첨가하지 않은 BiPbSrCaCuO계 초전도체와 2%의 산화은이 첨가된 시편의 자기부양 효과를 조사한 결과 pinning center의 역할이 중요함을 알 수 있다.

TFT의 게이트 전극을 형성하기 전에 소오스/드레인 이온 주입과 ELA를 수행함으로써 이온 주입에 의해 발생하는 결정 결함을 줄이는 새로운 poly-Si TFT를 제안한다. 한번의 ELA 공정을 통해서 채널 실리콘 박막의 결정화와 소오스/드레인의 불순물 활성화를 동시에 이루어 접합부의 결함을 치유하였고, 이온 주입에 의해서 비정질화된 소오스/드레인 실리콘과 채널 비정질 실리콘의 용융조건 차이를 이용하여 소오스/드레인 접합부에 실리콘 그레인의 수평성장을 유도하였다. 제안된 소자는 기존의 소자(이동도 : 86 $cm^2/V{\cdot}S$, ON/OFF 전류비 $6.1{\times}10^6$)에 비해 우수한 특성(이동도 : 171 $cm^2/V{\cdot}S$, ON/OFF 전류비 $4.1{\times}10^7$)을 나타내었다. LDD나 off-set 구조 없이도 소오스/드레인 접합부의 결함이 완전히 제거되어 누설전류가 감소하였고 소오스/드레인 접합부 결함이 있던 자리에 1 ${\mu}m$ 이상의 수평성장 그레인이 위치함으로써 ON 전류도 증가하여 ON/OFF 전류비가 크게 개선되었다.

The Displacement current measurement system used in this experiment because detecting the dynamic behavior of monolayers at the air-water interface is possible. It basically consists of a film balance, a pair of electrodes connected to each other through a sensitive ammeter. Here, one electrode is suspended in air and the other electrode is placed in the water. PBLG phase transformation measured by Maxwell-displacement-current-measurement method in surface of the water. Measured (surfacc pressure, displacement current and dipole moment) of monolayers of PBLG on the water surface. We measured displacement current that occur when changed temperature(15, 20, 25$^{\circ}$ ) and the compression speed(30, 40, 50(mm/min)). From the result, it is known that curren generated in the range of high surface pressur compression velocity and temperature become faste.

In order to examine the thermal properties of the wire materials, we analyzed the shrinkage, the expansion and the form transformation, the surface structure according to the thermal deterioration temperature through the testing method for a heating shrinkage of Korean Industrial Standard(KS C 3004). For IV(600V grade polyvinyl chloride insulated wires), we measured the shrinkage and the expansion rate, analyzed the surface structure using SEM(Scanning Electron Microscope). In the result of this experiment, the shrinkage rate of IV 2.0mm covering was high in comparison with other wires. As the deterioration temperature rises gradually, the covering is molten and harden.

Plasma polymerization of thiophene was carried out in a vacuum reactor with capacitively coupled electrode. This paper describes the dependence of molecular structure and electrical properties on the polymerization conditions such as plasma energy, mass flow rate and pressure. The plasma polymerized thiophene films were chracterized by FT-IR spectroscopy and SEM. The IR analysis revealed the thiophene rings are broken by the discharge energy.

EVA-OH (Ethylene-vinyl acetate-vinyl alchol terpolymers) were prepared by using the transesterification reaction between ethylene-vinyl acetate copolymer and alchol. Structural and thermal analyses were accomplished with FTIR and DSC. Space charge behaviors of EVA-OH were investigated using PEA method. Electrical conduction currents were also measured. As the increase of conversion rate, melting point increased and we could observe changes in space charge distributions and the increase of electrical conduction currents of EVA-OH.

Degree of crosslinking of insulation is very important factor that is determined characteristics of XLPE insulated power cable. Increase of degree of crosslinking is closely related to increase of mechanical characteristics of XLPE insulated power cable. In this study, mechanical characteristics of XLPE insulation for degree of crosslinking was analyzed tensile strength and elongation of insulation. As the result, mechanical characteristics of insulation for degree of crosslinking was divided three cases.

Polyaniline/polystyrene conducting blends were prepared and measured with the mechanical properties such as tensile strength and elongation and the electrcal properties such as surface resistance, electrical conductivity and dielectric loss tangent. The percolation threshold concentration of blends was 5phr of polyaniline and the morphology of blends was setting colser to that of polyaniline at higher concentration. The dielectric loss increased up to $10^5$ at the 50 % of polyaniline and was much influenced by frequency than temperature at higher concentration of polyaniline.

In this paper, we studied the characteristics of surface structure of phenolic resin by water treatment. Phenolic resin which is used as indoor insulators is easily deteriorated by humidity. Water treated sample for 200 hours is subjected to the penetration of water and cracked partially. Water treated sample for 400 hours is found more cracks than that for 200 hours. The initial leakage current of virgin sample is 0.11A, that of water treated sample for 200 hours is 0.07A, and that of water treated sample for 400 hours is 0.05A. FT-IR analysis indicates that absorption peak of carbonyl group appears in virgin sample, but the absorption peak does not appear in water treated sample for 200 hours.

The 400KN suspended insulator was fabricated with feldspar, quartz, clay and $Al_2O_3$ wt% for extra high voltage. These materials were grinded with ball milling for 25 hours after mixing them. The grinded materials were sintered at $1300^{\circ}C$ for 50 minutes in the tunnel kiln after mading with jiggering method. The sintered density of specimen was reached at 97% in comparison with that of theory. The specimen had the characteristic of temperature rise with the increase of electrical losses. Also, the flexural strength and the fracture toughness of sintered parts respectively were 1658 kg/$cm^2$ and 2.3 $MPa{\cdot}m^{1/2}$.

실리콘 고무는 내열성, 내후성, 발수성, 내오염성, 내트래킹성 등이 우수하여 옥외절연물용의 외피 재료로 널리 사용되고 있다. 폴리머 애자에서 전기방전 (코로나, 트래킹 등)에 의한 외피표면의 발수성 저하가 절연물의 장기성능에 있어서 가장 중요한 인자들 중에 하나이다. 실리콘 고무에는 ATH가 다량 첨가되는데 ATH의 첨가량, 표면처리상태, 입도 등에 의해 실리콘 고무의 발수성과 발수성회복 특성은 다르게 나타난다. 본 논문에서는 입도가 다른 2종의 ATH를 선택하여 실리콘 폴리머 대비 ATH의 첨가량을 달리하여 실리콘 고무의 발수성에 관련한 특성을 조사하였다. ATH의 입도 및 코로나 처리시간에 따라서 접촉각의 변화를 관찰하였으며, 코로나 처리 후 경과시간에 따른 발수성의 회복특성을 접촉각의 측정을 통하여 조사하였다.

폴리머 애자는 여러 가지의 외부환경에 의하여 시간의 경과에 따라서 재료의 열화가 진행된다. 폴리머 애자를 평가하는 방법으로 기계적 특성, 전기적 특성, 환경적 특성 등의 평가방법이 있으나 각각의 특성평가에 있어서 국제, 국가 및 단체에 따라서 서로 다르다. 신뢰성 평가기준도 서로 달라 국내 실정에 맞는 폴리머 애자의 신뢰성 향상에 어려움이 있었다. 이러한 문제를 해결하기 위하여 폴리머 애자의 신뢰성 평가기준을 표준화할 필요성이 있다. 본 원고에서는 특고압 가공배전선로에 사용하는 폴리머 현수애자의 신뢰성 평가기준에 대하여 설명하였다. 장기신뢰성 평가를 위하여 다양한 외부환경을 모의하여 복합적인 스트레스를 가할 수 있는 복합가속열화설비에 대하여 설명하고 복합가속열화시험법을 결정하였다.

내전압과 내아크성을 높이고 $SF_6$가스 내에서 복합재료로 사용된 유리섬유를 보호하기 위한 코팅 재료를 만들어서 특성을 평가하였다. 에폭시 수지에 내아크성이 우수한 무기물 필러인 $Al_2O_3$, $MgAl_2O_4$, BN, MgO 등을 첨가하여 절연저항, 유전특성, 내아크성 등의 전기적 특성을 평가하였다. 코로나 처리에 의한 열화를 평가하기 위하여 접촉각을 측정하고 전자현미경으로 표면의 상태를 관찰하였다.

The short-time permissible temperature of an overhead distribution line conductor is determined by the softening characteristics of ACSR-OC, ACSR AW/OC 160, typical conductors employed in the overhead distribution line. Transient heat transfer equation and Newton's cooling law were applied to analyze the heating and cooling effects of the insulating conductors, respectively, and the error of co-relation was calibrated after simulating the softening test to assess the short-time characteristic of the insulating conductor. In order to verify the softening characteristic, the conductors were tested with heat cycle. The test was totally carried out 200 cycles, and 1 cycle was to heat and cool at 1.1 times permissible current of the conductor, 1.15 times for 120 minutes, respectively. After heating, the tensile strength and surface of the conductor were observed. In case of ACSR-OC, as the result of 100 hour heating test, the tensile strength of the insulator was 0.8 times the initial value. This is equivalent to the value of the conductors which are used for 10 years at sites.

A developed 800kV class composite hollow insulator for $SF_6$ Gas Insulated Switchgear (GIS) was tested as to insulation with their surfaces contaminated. The wet power frequency withstand voltage of the silicone rubber housing was about 135kV at an equivalent salt deposite density of $5kg/m^2$, to sufficiently satisfy the required performance. According to IEC 60507, the salt fog withstand voltage was measured at 565kV, and the highest measured leakage current was below 0.2mA. Therefore, it was clarified that the composite hollow insulator has sufficient insulation performance even when it is contaminated on the surface.

Large turbine generator(rated 22kV) has failed in the stator winding area during normal operation. The capacitance and tan${\delta}$ were measured by Schering bridge in the zone 1, 2 and zone 3-6 stator windings. The capacitance and tan${\delta}$ in the zone 1, 2 of stator winding were higher than those of zone 3-6 in the stator winding. Experiments on microstructure property were conducted in the zone 1, 2 and zone 3-6 insulations, which were drawn out from stator windings of the large turbine generator. Microstructure analysis was characterized using scanning electron microscope(SEM). SEM results indicated that several isolated delaminations occurred at the interface of mica/epoxy insulations. Both thermal and mechanical aging cause the delamination.

The real-time dynamic rating system(DRS) can provide the maximum ampacity within required periods, so it can help the transmission-line operation more safely and efficiently. Because the conductor temperature is the main limit of increasing rating current, conductor temperature monitoring(CTM) technology is the basic to DRS. In this paper, real-time CTM was developed for 345kV XLPE cable in tunnel and we have also compared the CTM result of this study with the result according to IEC 287 and JCS 168 thermal parameters.

PE(Polyethylene)와 PP(Polypropylene)의 sheet 에 $Co^{60}{\gamma}$-ray 선원을 실온, 대기 중에서 10 kGy, 30 kGy, 50 kGy의 방사선량으로 조사시키고 습도 분포에 따른 표면 및 체적 저항을 측정한 결과 방사선이 조사되지 않은 시료와 방사선이 조사된 시료와의 저항 값은 큰 차이를 보이지 않았으나 습도 효과에 따른 변화는 습도 분포가 높을수록 저항 값은 상대적으로 낮게 나타났다.

The test methods on materials of electrical power cable are used in accordance with 25 specifications of IEC, ASTM, ICEA, KS and KEPCO Spec. The validation of test methods were checked and stablished by solving the problems occurred during the test. These tests are flammability, degree of acidity of gases, amount of halogen acid gas, smoke density, oxygen index, amount of ion in semiconductor, void, amber, contaminant and water tree, crosslinked density. Then the performance of power cable made by A, B, C and D company were evaluated and compared.

In this paper, the thermal analysis and dielectric/insulation properties were investigated with considering the temperature depenence Using the sheet of semi-conductor/XLPE came from 22 kV power cables, the dielectric/insulation properties and temperature dependence were measured under 1kHz. According to the results we can verify that only semi-conductor sheet changed linearly, and with the unstable results. the dielectric/insulation properties of the semi-conductor/XLPE sheet show the highest value in the range of 40 $^{\circ}C$ and 50 $^{\circ}C$ and are rely on XLPE rather than semi-conductor in terms of the temperature.

This paper aims to investigate the characteristics of braided thermoplastic and thermosetting composite and pressure relief for polymer arrester. In general, braided composite has potential for improved impact and delamination resistance. Manufacturing processes of the braided composite could also be automated and could potentially lead to lower costs. Therefore, in consideration of characteristics of pressure relief for polymer arrester, the fabric pattern of braided composite was studied. And polymer arrester module was manufactured with braid.

3원계 51wt%Ni-4lwt%Cr-8wt%Si 합금 타겟을 가지고 DC/RF 마그네트론 스퍼터를 이용하여 박막저항을 제조하였고, 낮은 저항온도계수(TCR)를 가지는 박막을 만들기 위해 제조공정의 변화에 따른 박막의 미세구조와 전기적인 특성을 조사하였다. 스퍼터링 제조공정 변수로써 DC/RF Power, 반응압력, 기판온도를 변화시켰고, 제조된 박막은 공기중에서 $400[^{\circ}C]$까지 열처리 하였다. 반응압력을 감소시킴에 따라 TCR값은 감소하였고, 기판온도 및 열처리 온도의 증가에 따라 TCR값도 증가하였다. 또한, 비저항은 DC Power에서 $172[{\mu}{\Omega}cm]$, RF인 경우에는 $209[{\mu}{\Omega}cm]$을 나타내었고, 각각 +52, $-25[ppm/^{\circ}C]$의 TCR값을 나타냈다. 이와 같은 결과로부터 제조공정을 변화시킴에 따라 면저항 및 저항온도계수의 제어가 가능함을 알 수 있었다.

This study presents the dielectric properties of $Ta_2O_5$ MIM capacitor structure processed by thermal oxidation. The AES(auger electron emission) depth profile showed thermal oxidation effect gives rise to the $O_2$ deficiened into the new layer. The leakage current density respectively, at $1{\sim}3{\times}10^{-3}$(kV/cm) were $3{\times}10^{-4}-10^{-8}(A/cm^2)$. Leakage current density behavior is stable irrespective of applied electric field, the frequency va capacitance characteristic enhanced stability. The capacitance vs voltage measurement that, $V_{fb}$(flat-band voltage) was increase dependance on the thin films thickness, it is changed negative to positive.

In recent years, the tantalum nitride(TaN) thin-film has been developed for the electronic resistor, inductor and capacitor. In this papers, this study presents the surface profile and sheet-resistance property relationship of reactive-sputtered TaN thin film resistor processed by TaN(tantalum nitride) on alumina substrate. The TCR properties of the TaN films were discussed in terms of crystallization and thin films surface morphology due to annealing temperature. It is clear that the TaN thin-films resistor electrical properties are low TCR related with it's annealing temperature and ambient annealing condition. Respectively, at $300{\sim}400^{\circ}C$ on vacuum and nitrogen annealed thin film resistor having a goof thermal stability and lower TCR properties then as deposited thin films expected for the application to the dielectric material of passive component.

AlN thin films were deposited on Si(100) and $SiO_2$/Si substrates using R.F. magnetron sputtering system. The effect of various deposition conditions on the crystal orientation of AlN films was investigated to obtain a highly (002)-oriented films. SAW filters were fabricated using AlN films with various thicknesses and their frequency response characterizations were measured. Experimental results showed that the (002)-orientation and surface roughness of AlN films played a crucial role of determining the frequency response of AlN SAW devices.

Transparent conductive oxides (TCO) are necessary as front electrode for most thin film solar cell. In our paper, transparent conducting aluminum-doped Zinc oxide films (ZnO:Al) were prepared by rf magnetron sputtering on glass (Corning 1737) substrate as a variation of the deposition condition. After deposition, the smooth ZnO:Al films were etched in diluted HCI (0.5%) to examine the electrical and surface morphology properties as a variation of the time. The most important deposition condition of surface-textured ZnO films by chemical etching is the processing pressure and the substrate temperature. In low pressures (0.9mTorr) and high substrate temperatures $({\leq}300^{\circ}C)$, the surface morphology of films exhibits a more dense and compact film structure with effective light-trapping to apply the silicon thin film solar cells.

The 0.96Mg$TiO_3$-0.04Sr$TiO_3$ ceramics with $V_2O_5$(5wt%) were prepared by the conventional mixed oxide method. The structural properties were investigated with sintering temperature by XRD and SEM. According to the X-ray diffraction patterns of the 0.96Mg$TiO_3$-0.04Sr$TiO_3$ceramics with $V_2O_5$(5wt%), the ilmenite $MgTiO_3$ and perovskite $SrTiO_3$ structures were coexisted and secondary phase $MgTi_2O_5$ were appeared. Increasing the sintering temperature, the grain size was increased and three types of grains were exhibited: larger circular grain, small square grain and lapth-shaped grain. In the case of 0.96Mg$TiO_3$-0.04Sr$TiO_3$ ceramics with $V_2O_5$(10wt%), dielectric constant, quality factor and temperature coefficient of resonant frequency were $15.24{\sim}18.55$, $22,890{\sim}42,100$GHz, -24.5${\sim}$+2.414ppm/$^{\circ}C$, respectively.

The (Bi,Ba,Sr)$TiO_3$[BBST] thin films were fabricated on Pt/Ti/$SiO_2$/Si substrate by RF sputtering method. We investigated the effects of Ar/$O_2$ rates on the structural properties of BBST thin films. Decreasing the $O_2$ rates, the intensity of $BaBi_4Ti_4O_{15}$ and $Bi_4Ti_3O_{12}$ peaks were increased but the $(Ba_{0.5}Sr_{0.5})TiO_3$ peak was decreased. In the case of BBST thin films deposited with condition of 90/10 (Ar/$O_2$) ratio, the composition of Ba/Sr/Bi was 0.35/0.4/0.25. Also, in the BBST thin films deposited with condition of 80/20(Ar/$O_2$) ratio, the composition of Br,Sr and Ti were relatively uniform. But the component of Bi and Ti were diffused into the Pt layers.

The 0.5$Ba_2Ti_9O_{20}$-0.5Mg$TiO_3$ ceramics were prepared by the conventional mixed oxide method. The structural properties were investigated with sintering temperature by XRD. According to the X-ray diffraction patterns, major phases of the 0.5$Ba_2Ti_9O_{20}$-0.5Mg$TiO_3$ ceramics were coexisted. Also the secondary phase of Mg$Ti_2O_5$, Ba$Mg_6Ti_6O_{19}$ and the unreacted $TiO_2$ phase were existed. In the case of 0.5$Ba_2Ti_9O_{20}$-0.5Mg$TiO_3$ ceramics sintered $1350^{\circ}C$, dielectric constant, quality factor and temperature coefficient of resonant frequency were 33.7, 54,900GHz, -12.5ppm/$^{\circ}C$, respectively.

내열 충격성 및 적외선 투과를 갖는 LAS($Li_2O-Al_2O_3-SiO_2$)계 글라스세라믹스를 제조하였다. 본 연구에서는 LAS계에 $TiO_2$를 핵형성제로, 점도를 감소시키기 위해 $P_2O_5$를 첨가하여 유리를 제조한 후, 글라스세라믹 결정상을 석출시켰다. 석출된 주 결정상은 ${\beta}$-eucryptite(SS)이었으며, 열팽창 계수가 거의 제로에 가까운 값을 얻었다. 또한 선택적인 스펙트럼의 흡수를 위한 color dopants에 대한 기초 자료 등이 조사되었다.

본 논문에서는 세라믹 다이어프램식 압력센서를 설계하기 전에 세라믹 다이어프램의 변위에 대한 최적 조건을 확립하기 위해 세라믹의 기계적 특성, 다이어프램의 두께와 직경 등을 변화시키면서 중심부와 변곡점 부근에서 압력에 대한 다이어프램의 변위를 시뮬레이션 하였으며 결과를 이용하여 세라믹 다이어프램을 이용하고 후막저항을 센싱 부분으로 하여 4가지 형태의 기하학적인 출력특성을 고찰하였다.

In this paper, we proposed windmill type ultrasonic motor which has modified shape of Endcap. The motor was especially designed by FEM for high speed. As results, displacements of the windmill and the clover type motor was compared. Using clover type motor, more smooth rotation of rotor was achieved. If Z component of the displacement of the clover type motor can be applied for linear motor.

$(Ba_{0.6-x}-Sr_{0.4}Ca_x)TiO_3$ (x=0.10, 0.15, 0.20, y=$0.0{\sim}3.0$) powders were fabricated by the sol-gel method, and BSCT thick films were fabricated by the silk-screen printing method. Their structural and dielectric properties were investigated with variation of composition ratio. All BSCT thick films showed a homogeneous structure without presence of the second phase. BSCT film thickness, obtained by three cycle of printing, was approximately $80{\mu}m$. The dielectric constant and dielectric loss of the 3-coated BSCT(50/40/10) thick film were approximately 1700 and 0.07%, respectively.

In this study linear and nonlinear formula were deduced clearly in cases of the free rotational dipole theory and the phenomenological response theory and practical usefullness of formula by these two theories was discussed.

This paper presents design and construct of flat type step-down piezoelectric transformer for the application to AC adaptor. This piezoelectric transformer operated in resonance vibration mode. In this paper, finite element method(FEM) was used for analysing piezoelectric transformers. Stress and electric field of the transformer were simulated at resonance frequency. Using this simulation results, we manufactured improved Rosen type piezoelecric transfomer and measured its output characteristics. As results, output power was linearly increased by increasing input power at resonance frequency and it was found that the transformer an invariable output power for input power. From these results, we expect that this piezoelecric transfomer can be applied to small size and low capacitive AC adaptor.

$MnO_2$ is used for the oxide electrode of electrochemical equipments because of its good electric conductivity and low oxygen overpotential. The effect of additives on the properties of $MnO_2$ has been investigated to enhance the electric conductivity and the stability in an acid solution. In this research, the effect of Ni addition on ${\beta}-MnO_2$ was studied by the theoretical quantum chemical method. The calculation was carried out by the discrete variation $X{\alpha}$ method, which is a sort of the first principle method and use Hatre-Fock-Slater approximation. The electron energy level, the density of state, the bond overlap population, the charge density distribution and the net ionic transfer between cations and anions were calculated and discussed. The used cluster model was $(Mn_{10}NiO_{44})^{-44}$.

Purpose of this research compares best transfer speed about applied frequency and voltage using characteristic of $L_1-B_4$ mode and $L_1-B_8$ mode linear ultrasonic motor that use piezoelectric effect. By method of study, analyzed best transfer speed measuring and comparison load status that use actuality telephone card in $L_1-B_4$ mode linear ultrasonic motor and no-load status of $L_1-B_8$ mode linear ultrasonic motor. Experiment result is applied frequency(58.4Hz) in $L_1-B_4$ mode linear ultrasonic motor (load state) and the best transfer speed by 19.8[cm/s] at applied voltage(56V) point. Also, $L_1-B_8$ mode linear ultrasonic motor (no-load state) is best transfer speed by applied frequency(27.9kHz) and 32.96[cm/s] at applied voltage (50V) point.

본 논문에서는 1.58 ${\times}$ 0.82 ${\times}$ 0.94 $mm^3$크기의 H 형태의 솔레노이드형 RF 칩 인덕터를 코일의 직경과 권선수를 변화시키면서 제작하였고, 그들의 고주파 성능을 비교 분석하였다. 저손실 $Al_2O_3$재료를 코아로 $30{\mu}m{\sim}40{\mu}m$의 여러 직경을 가진 Cu를 코일로 사용하였다. 인덕터의 인덕턴스(L), 품질계수(Q), 저항(R), 임피던스(Z) 그리고 커패시턴스(C) 등의 주파수 특성은 HP4291B로 측정하였다. 실험결과 동일권선수에 대해 코일직경이 자을수록 L, Q, R, 그리고 Z등이 증가하였고, 그 증가폭은 권선수가 클수록 커지는 경향이 있음을 알 수 있었다. 그러나 코일직경이 작을수록 기생 커패시턴스 효과가 빨리 나타나 자기 공진주파수 효과가 감소하는 경향을 보이고 있음을 확인하였다. 코일직경이 $3{\mu}m$이고 권선수가 6인 경우에 대표적인 값들은 다음과 같다. L=31.4nH(at 250MHz), Q=49.6(at 700MHz), R=0.362${\Omega}$(at 1MHz)

본 논문에서는 $1.62{\times}1.0{\times}0.88mm^3$ 크기의 C-type과 $1.58{\times}0.82{\times}0.94mm^3$ 크기의 H-type RF 칩 인덕터를 제작하고 그들의 고주파 특성을 비교하였다. 본 연구에서는 저손실 $Al_2O_3$ 코아 물질과 직경 $40{\mu}m$의 구리(Cu) 코일을 사용하였다. 권선수를 $2{\sim}14$회로 하여 인덕턴스(L), 품질계수(Q), 임피던스의 크기와 위상, 커패시턴스(C)를 HP4291B Impedance/Material Analyzer로 측정하였다. 10회 권선시 C-type은 55nH, H-type은 67nH, 14회 권선시 C-type은 100nH, H-type은 122nH 정도로 측정되었다. 실험 결과 H-type이 C-type보다 동일 권선수에 대하여 높은 인덕턴스와 높은 자기공진주파수(SRF)를 나타냄을 확인하였다. 또한 최대 품질계수는 두 형태가 거의 비슷한 값($55{\sim}87$)을 가짐을 관찰하였다. 따라서 H-type이 C-type보다 우수한 성질을 나타냄을 알 수 있다.

본 논문은 저손실 소형 대역통과 여파기인 기지국용 RF/Microwave 수동소자의 다중 공진 모드(Multi-Mode)에 관한 연구로 한개의 유전체 공진기(Dielectric Resonator)로 두개의 공진 모드(Dual-Mode)를 형성하고 그의 결합량을 조절하여 대역통과 여파기를 설계 및 제작하고, 기지국용 Dual-Mode 대역통과 여파기의 소형화, 경량화를 50%이상 향상시켜 양질의 Dual-Mode 공진 특성을 관찰하였다.

전력선 통신 시스템을 간략히 살펴보면 송전단과 수전단으로 나누어 볼 수 있다. 송전단은 전력을 송전하기 위한 설비와 신호를 싣고 분리하는 결합회로로 구성되며 수전단은 수전설비와 결합회로로 분리된다. 결합회로는 $BaTiO_3$를 주성분으로 하는 고유전율 및 대용량의 캐패시터로 구성되었다. 이 캐패시터를 변압기 외부에 사용하므로, 직사광선에 의한 온도 변화가 생길 것이며 이 변화에 따라 캐패시턴스 값의 변화가 생길 것이므로 HPF로 사용할 때 캐패시턴스 값의 변화로 주파수에 영향을 줄 것이다. 주위온도에 따른 캐패시턴스의 변화가 HPF의 동작에 어떠한 영향을 미치는지 고찰하고자한다. 이에 본 연구에서는 수전단의 10KV이하 배전 선로에 사용되는 Coupling Capacitor의 외부온도를 변화시켜 전기적 특성의 변화를 고찰함으로서, HPF로서의 사용될수 있는지 확인하고자 한다.

Carbon nanotubes (CNTs) were grown with high density on a large area of Ni-coated silicon oxide substrates by using an inductively coupled plasma-chemical vapor deposition (ICP-CVD) of $C_2H_2$ at temperatures ranging from 600 to $700^{\circ}C$. The Ni catalyst was formed using an RF magnetron sputtering system with varying the operating pressure and exposure time of $NH_3$ plasma. The surface morphology of nickel catalyst films and CNTs was examined by SEM and AFM. The graphitized structure of CNTs was confirmed by Ramman spectra, SEM, and TEM. The growth of CNTs was observed to be strongly influenced by the surface morphology of Ni catalyst, which depended on the pre-treatment time and growth temperature. Dense CNTs with uniform-sized grains were successfully grown by ICP-CVD.

Effects at thermal treatment on the structural and electrical properties at DLC films have been studied. The DLC films were deposited by using a modified FCVA system as a function at negative substrate bias voltage, deposition time, and nitrogen flow rate. The thermal treatment on DLC films could be achieved by performing the RTA process at $600^{\circ}C$, 2min. Structural investigation on the thermal treatment effect was evaluated by inspecting the Raman spectroscopy, XPS, AFM, and internal compressive stress. In addition, the electrical properties of DLC films were evaluated by using the high current source and Lab-View data acquisition system. As the result at RTA treatment, $sp^3/sp^2$ ratio and internal compressive stress of the DLC films were decreased tram 5% to 22% and from 1GPa to 3GPa, and the $I_D/I_G$ intensity ratios was increased from 0.19 to 0.35. It was also found that the variation of internal stress of DLC films strongly agree with the variation of $sp^3/sp^2$ fraction and $I_D/I_G$ intensity ratio.

When did Metal (Au, Al) electrode differently, it is spread already that it is by energy level of electrode difference of electrical conductivity. This paper, experiment manufactures device of Metal/Organic Films/Metal structure using PBDG and I-V properties by electrode analyzed comparison. Also, measure energy level by electrode by propertiesy electrochemistry and studied about electron transfer of organic thin film in LUMO level relation with HOMO level.

Experimental works were performed to implement the hetero-epitaxial growth of diamond films on the (100)- and (111)-oriented Si substrates. The deposition process used to prepare diamond films consisted of a bias-enhanced nucleation(BEN) step, accompanied with a growth step using a microwave plasma CVD system. The highly oriented diamond films were deposited under the growth condition of relatively low methane concentrations and high temperatures. Material properties and surface morphologies of deposited diamond films were improved by the addition of carburization step into the deposition process.

In this paper, the electrical characteristics of pentacene thin film transistors(TFTs) with stacked and surface-treated gate insulators have been investigated. The semiconductor layer of pentacene was thermally evaporated onto the stacked gate insulators. For the gate insulating materials. PVP(PolyvinylPhenol) and polystyrene were spin-coated with two different stacking orders, PVP-polystyrene and polystyrene-PVP. Rapid solvent evaporation during the spin-coating processes of these insulating layers produces non-equilibrium phase morphologies accompanied by surface undulations on gate insulator interfaces. This non-equilibrium phase morphology affects the growth mode of the subsequent pentacene layer. Therefore, in order to smoothen the gate dielectric surfaces, gate dielectric surfaces were rubbed laterally along the direction from the drain to the source TFTs with with stacked and surface-treated gate insulators have provided improved operational characteristics.

현재 게이트 길이가 100nm 이하의 MOSFET 소자를 구현할 때 가장 대두되는 문제인 short channel effect를 억제하는 방법으로 제안된 소자 중 하나가 double gate (DG) silicon-on-insulator (SOI) MOSFET이다. 그러나 DG SOI MOSFET는 두 게이트간의 align과 threshold voltage control 문제가 있다. 본 논문에서는 DG SOI MOSFET에서 이상적으로 게이트가 align된 구조와 back 게이트가 front 게이트보다 긴 non-align된 구조가 subthreshold 동작 영역에서 impact ionization에 미치는 영향에 대해 시뮬레이션을 통하여 비교 분석하였다. 그 결과 게이트가 이상적으로 align된 구조보다 back 게이트가 front 게이트보다 긴 non-align된 구조가 게이트와 드레인이 overlap된 영역에서 impact ionization이 증가하였으며 게이트가 각각 n+ 폴리실리콘과 p+ 폴리실리콘을 가진 소자에서 두 게이트가 같은 work function을 가진 소자보다 높은 impact generation rate을 가짐을 알 수 있었다.

본 논문에서는 실리콘을 기초로 한 포토다이오드를 제작하여 현재 바이오센서에서 이용되고 있는 luminol 화학 발광을 전기적으로 검출하였다. 우선, 실리콘 웨이퍼에 이온주입을 통해 p-n 접합을 형성하고 Al 전극을 형성시켜 포토다이오드를 제작하였다. PDMS을 passivation 막으로 사용하여 horseradish peroxidase(HRP) 농도 변화에 따른 발광의 최적조건과 luminol, HRP가 섞인 용액에 서로 다른 양의 과산화수소를 넣어 발광이 최대로 발생하는 혼합비를 측정하였다. 최종적으로 2mM luminol, 25U HRP 조건 하에서 과산화수소 농도에 따른 화학 발광을 측정하였으며, $10{\mu}M$부터 $500{\mu}M$ 범위의 과산화수소 농도 변화에 따른 포토다이오드의 감도는 단위 면적당 23.429pA/ ${\mu}M$이다.

This paper presents deposition and characterizations of microcrystalline silicon(${\mu}c$-Si:H) films prepared by hot wire chemical vapor deposition at substrate temperature below $300^{\circ}C$. The $SiH_4$ Concentration$[F(SiH_4)/F(SiH_4)+F(H_2)]$ is critical parameter for the formation of Si films with microcrystalline phase. At 6% of silane concentration, deposited intrinsic ${\mu}c$-Si:H films shows sufficiently low dark conductivity and high photo sensitivity for solar cell applications. P-type ${\mu}c$-S:H films deposited by Hot-Wire CVD also shows good electrical properties by varying the rate of $B_2H_6$ to $SiH_4$ gas. The solar cells with structure of Al/nip ${\mu}c$-Si:H/TCO/glass was fabricated with sing1e chamber Hot-Wire CVD. About 3% solar efficiency was obtained and applicability of HWCVD for thin film solar cells was proven in this research.

적외선 확산반사형 결정화유리를 응용한 레이저 여기용 공진기를 제작하여 미세구조 분석 및 레이저 여기 효율특성을 조사하였다. 출발물질로는 Cordierite를 주결정상으로 하는 MAS(MgO, $Al_2O_3$, $SiO_2$) 3성분계 조성에 결정화 유도용 조핵제로 $TiO_2$를 첨가하였으며, 형성된 유리 용융물을 흑연제 몰드에 부어 공진기를 제조하였다. 용융물 중 일부를 2단계 열처리를 행하여 상분석을 실시한 결과 Cordierite($2MgO{\cdot}2Al_2O_3{\cdot}5SiO_2$)와 Rutile($TiO_2$)이 주결정상으로 관찰되었으며, 열처리 온도를 변화시켜 생성된 입자의 크기에 따른 확산반사율간의 관계를 조사한 결과, $1100{\sim}1200nm$에서 열처리된 시편의 경우 $500{\sim}2200nm$의 영역에서 95% 이상의 확산반사율을 나타내었다. 대표적인 고체레이저인 Nd:YAG의 경우, $700{\sim}900nm$ 파장이 주흡수대이며, 이를 결정화유리로 제조된 공진기의 레이저 효율특성실험에 이용하였다. 수냉 및 단일 펄스의 조건에서 $1.7{\sim}1.9%$의 효율을 나타내었다.

속중성자 피폭 시 실리콘 다이오드 내부에서 발생되는 변위 손상을 이용한 속중성자 탐지용 PIN 다이오드를 개발하고 중성자장에서 특성변화 및 감도 실험을 통하여 성능을 검증하였다. 시뮬레이션과 다양한 구조로 제작된 소자에 대한 방사선 실험을 거쳐 집합체 형태와 개별 PIN 다이오드를 제작한 다음 중성자 반응 특성과 감도 분석을 위한 중성자 방사선 실험을 수행하였다. 여러 개의 PIN 다이오드 샘플에 대한 중성자 특성변화를 실시간으로 측정하기 위해 디지털 정전류 구동 방식의 온라인 전자적 선량계 모듈을 제작하여 사용한 실험의 결과. 본 연구에서 개발한 PIN 다이오드 소자는 중성자 방사선에 대하여 우수한 감도 특성을 갖는다는 것과 입사 중성자에 대한 방향 의존성이 거의 없다는 사실을 알 수 있었다. 그리고 이어 수행된 300여 시간의 열화실험을 통하여 본 연구에서 제작된 PIN 다이오드 소자는 중성자 탐지소자로서의 사용 가능성이 충분함을 확인할 수 있었다.

본 논문은 혈당, 콜레스테롤센서에 적용이 가능한 과산화수소($H_2O_2$) 검출방식인 전기화학발광(Electrochemiluminescence:ECL)법 사용에 필요한 전극특성에 관한 연구이다. 전기화학전극으로 Pt박막전극을 사용하였으며, luminol(5-amino-2, 3-dihydro-1, 4-phthala edione)과 과산화수소($H_2O_2$)의 반응으로 발생한 빛을 포토다이오드(photodiode)를 사용하여 전류를 측정하였다. 사용된 전극은 직사각형(rectangular-type), 교차형(interdigitated-type)의 두 가지 형태를 사용하여, 전극간의 거리와 면적에 따른 ECL특성을 측정하였다. ECL 발광 특성은 전극 면적이 증가함에 따라, 전극거리가 감소함에 따라 증가함을 관찰할 수 있었다.

The determination of DNA hybridization can apply the molecular biology research, clinic diagnostics, bioengineering, environment monitoring, food science and other application area. So, The determination of hybridization is very important for the improvement of DNA detection system. In this study, we report the characterization of the DNA hybridization by the electricalchemical methods. A new electrochemical biosensor is described for voltammetric detection of gene sequence related to probe oligonucleotide of bacterium Escherichia coli O157:H7. The biosensor involves the immobilization of a 18-mer probe oligonucleotide, which is complemetary to a specific gene sequence related to Escherichia coli O157:H7 on a gold electrode through specific adsorption. The probe oligonucleotide was used to determine the amount of target oligonucleotide in solution using mitoxantrone(MTX) as the electrochemical indicators. The cathodic peak currents $(I_{peak})$ of MTX were linearly related to the concentration of the target oligonucleotide sequence in the range $1[{\mu}M]{\sim}0.1[nM]$. The detection limit of this approach was 0.01[nM]. In addition, these indicators were capable of selectivity discriminating against various mismatching condition.

In this paper, we discuss the electrical properties of self-assembled (2'-amino-4,4-di(ethynylp henyl)-5'-nitro-1-(thioacetyl)benzene), which has been well known as a conducting molecule having possible application to molecular level NDR device. The phenomenon of negative differential resi(NDR) is characterized by decreasing current th a junction at increasing voltage, also fabricatio MIM-type molecular electronic device and the Molecular Level Using Scanning Tunneling Microscopy.

In this study, multi layer type OLED(Organic Light Emitting Diode) has been fabricated using $Snq_2$, $Snq_4$, and $Alq_3$ for development of high efficiency, electrical and optical properties of multi layer type OLED investigated. The HTL(Hole Transfer Layer) and EML(Emitting Material Layer) were fabricated by using vacuum evaporation on ITO electrode, and its thickness controlled using thickness monitor. Al was used as a cathode. The electrical and optical properties such as J-V, brightness-V and EL spectrum of OLED device was measured using I.V.L.T system. The result, brightness of $Alq_3$, $Snq_2$ and $Snq_4$ were $3900cd/m^2$, $63cd/m^2$ and $23cd/m^2$ respectively.

The breakdown and on-state characteristics of the multi-RESURF SOI LDMOSFET is presented. P-/n-epi layer thickness and doping concentration is varied from $2{\mu}m{\sim}5{\mu}m$ and $1{\times}10^{15}/cm^3{\sim}9{\times}10^{15}/cm^3$ to obtain optimum breakdown voltage and on-resistance. The breakdown and on-state characteristics of the device is verified by two-dimensional process simulator ATHENA and device simulator ATLAS.

본 논문은 다공질 실리콘 다이어프램에 대한 화학 센서의 일종인 습도, 에탄올, 메탄올의 감지 특성을 측정하고 전기 전도도의 변화를 고찰하였다. 먼저, TMAH 용액으로 실리콘 다이어프램을 제작한 후, HF와 에탄올의 혼합 용액내에서 일정 전압을 인가하여 다공질 실리콘 다이어프램을 형성하였다. 다공질 실리콘을 면(100)에 수직한 방향으로 $50{\sim}100{\mu}m$ 두께로 균일하게 형성하여 p+-PSi-n+ 구조의 소자를 제작하였다. 다공질 실리콘 다이어프램의 절대습도에 대한 감도는 입력 주파수 5kHz에서 인가 전압이 $2{\sim}6$Vpp에서 $376.3{\sim}784.8{\Omega}$/%RH으로 변하였다. 또, 인가 전압 6Vpp에서 입력 주파수가 $2{\sim}5$kHz으로 변할 때 $393.3{\sim}784.8{\Omega}$/%RH으로 변하였다. 또한, 에탄올에 대한 감도는 $0.068{\mu}A$/%이며, 메탄올은 $0.212{\mu}A$/%으로 다공질 실리콘 다이어프램은 에탄올 보다 메탄올이 더 민감하게 반응하였다. 일반적으로 다공질 실리콘의 전기전도도는 charged surface traps과 screening effect에 의존한다.

CuIn$Se_2$ (CIS) and related compounds such as Cu($In_xGa_{1-x})Se_2$(CIGS) have been studied by their potential for use in photovoltaic devices. CIS thin film materials which have high absorption coefficient and wide bandgap, have attracted much attention as an alternative to crystalline and amorphous silicon solar cells currently in use. Cu-rich CIGS film have very low resistivity, due to coexistence of the semimetallic $Cu_{2-x}Se$. In-rich CIGS films show high resistivity, since these films are compensated films without the $Cu_{2-x}Se$ phase. Optical properties of the CIGS films also change in accordance with the resistivity for the Cu/(In+Ga) ratio. The Cu-rich films have different spectra from In-rich films in near infrared wavelengths.

Photovoltaics is considered as one of the most promising new energy technology, because its energy source is omni present, pollution-free and inexhaustive. It is agreed that these solar cells must be thin film type because thin film process is cost-efficive in the fact that it uses much less raw materials and can be continuous. The defect chalcopyrite material $CuIn_3Se_5$ has been identified as playing an essential role in efficient photovoltaic action in $CuInSe_2$-based devicesm It has been reported to be of n-type conductivity, forming a p-n junction with its p-type counterpart CuInSe2. Because the most efficient cells consist of the $Cu(In,Ga)Se_2$ quarternary, knowledge of some physical properties of the Ga-containing defect chalcopyrite $Cu(In,Ga)_3Se_5$ may help us better understand the junction phenomena in such devices.

In this work the electrical characteristics of organic TFTs using organic insulator and flexible polyester substrate have been investigated. Pentacene and PVP(polyvinylphenol) are used as an active semiconducting layer and dielectric layer respectively. Pentacene was thermally evaporated in vacuum at a pressure of about $1{\times}10^{-6}$ Torr and at a deposition rate of $0.5{\AA}$/sec, and PVP was spin-coated. Aluminium and gold were used for gate and source/drain electrodes. 0.1mm thick flexible polyester substrate was used instead of glass or silicon wafer.

Single crystal 3C-SiC(cubic silicon carbide) thin-films were deposited on Si(100) wafers up to a thickness of 4.3 ${\mu}m$ by APCVD method using HMDS(hexamethyildisilane) at $1350^{\circ}C$. The HMDS flow rate was 0.5 sccm and the carrier gas flow rate was 2.5 slm. The HMDS flow rate was important to get a mirror-like crystal surface. The growth rate of the 3C-SiC films was 4.3 ${\mu}m/hr$. The 3C-SiC epitaxial films grown on Si(100) were characterized by XRD, AFM, RHEED, XPS and raman scattering, respectively. The 3C-SiC distinct phonons of TO(transverse optical) near 796 $cm^{-1}$ and LO(longitudinal optical) near $974{\pm}1cm^{-1}$ were recorded by raman scattering measurement. The hetero-epitaxially grown films were identified as the single crystal 3C-SiC phase by XRD spectra($2{\theta}=41.5^{\circ}$).

This paper presents the characteristics of Ta-N thin-film strain gauges as high-temperature strain gauges, which were deposited on Si substrate by DC reactive magnetron sputtering in an argon-nitrogen atmosphere(Ar-($4{\sim}16%$)$N_2$). These films were annealed for 1 hour in $2{\times}10^{-6}$ Torr vacuum furnace range $500{\sim}1000^{\circ}C$. The optimized conditions of Ta-N thin-film strain gauges were annealing condition($900^{\circ}C$, 1 hr.) in 8% $N_2$ gas flow ratio deposition atmosphere. Under optimum conditions, the Ta-N thin-films for strain gauges is obtained a high resistivity, ${\rho}$=768.93 ${\mu}{\Omega}cm$, a low temperature coefficient of resistance, TCR = -84 ppm/$^{\circ}C$ and a high temporal stability with a good longitudinal gauge factor, GF = 4.12.

$Zn_4SnSe_6$ and $Zn_4SnSe_6:Co^{2+}$ single crystals were by the chemical transport reaction method. They crystallized in the monoclinic structure. The direct energy band gaps of the $Zn_4SnSe_6$ and $Zn_4SnSe_6:Co^{2+}$ single crystals at 289K were found to be 2.146eV and 2.042eV. Optical absorption due to impurity in the $Zn_4SnSe_6:Co^{2+}$ single crystal was observed and described as originating from the electron transition between energy leveles of $Co^{2+}$ sited at $T_d$ symmetry point.

TFT-LCD is widely used for flat panel display. The large-size TFT-LCD panel requires a high speed driving and various driving methods because of signal delay, which is responsible for the shading effects. In this work, the floating and double driving methods are applied to Pixel Design Array Simulation Tool(PDAST) and the pixel characteristics of TFT-LCD array is simulated. Also, we have implemented the semi-empirical TFT model to PDAST, which makes to obtain a more accurate pixel characteristics.

The triac is a bidirectional triode with blocking and conducting characteristics used in motor control or heater power control. This greatly simplifies the circuits required for the control of the full wave AC Power by reducing the number of power handling components and by reducing the size and complexity of the gate control circuit.[3] In this paper, We can understand measurement results of analysis which have been made on the electrical characteristics of triac with gate diffusion time for the gate area.

Multi-layer organic electroluminescent(EL) devices with Al-CsF composite as a cathode were fabricated. This device privides low driving voltage and high quantum efficiency. CsF is evaporated onto and diffuse into electron transport layer. $Alq_3$. The Fermi level of $Alq_3$ moves towards the LUMO level.

본 논문에서는 엑시머 레이저 조사에 의한 이온 농도의 분포 변화를 알아보기 위해 붕소 이온이 선택적으로 주입된 비정질 실리콘 박막 위에 XeCl (${\lambda}$=308nm) 엑시머 레이저를 조사하여 붕소이온의 수평 확산 현상을 관찰하였다. 도핑 농도의 분포를 알아보기 위해 불산/질산 용액에 의한 고농도 도핑 영역의 습식 식각을 이용하여 약 $10^{18}/cm^3$ 이하의 붕소이온을 가지는 실리콘 박막의 형태를 전자주사 현미경을 이용해서 관찰하였다. 실험 결과, $200mJ/cm^2$의 레이저 에너지가 조사될 경우, 약 100nm의 수평 확산이 일어났음을 확인 할 수 있었다.

본 논문은 얇은 실리콘 산화막 트렌치를 이용하여 같은 항복 전압에서 면적을 줄이는 접합 마감(junction termination)을 제안하였다. 제안된 P+FLR(Floating Field Ring) 구조는 기존 P+ FLR구조에 비해 항복 전압 571 V에서 면적을 83 %로 감소시켜 접합 마감 특성이 개선되었다.

Transformation of molecular film occurs only usually in air-water interface, 2 dimensions domain's growth and crash are achieved. Organic matter thin film that accumulate molecular film in archaism board only that consist of growth of domain can understand correct special quality of accumulation film supplying information about fine structure and properties of matter of device observing information and so on that is surface forward player and optic enemy using AFM one of SPM application by nano electronics. The stable images are probably due to a strong interaction between the monolayer film and glass substrate. We are unable to obtain molecule resolution in images of the films but did see a marked contrast between images of the bare substrate and those with the network structure film deposited onto it. Formation that prevent when gas phase state and liquid phase state measure but Could know organic matter that molecules form equal and stable film when molecules were not distributed evenly, and accumulated in solid state only.

If the ambient temperature rises in AC PDP, some of the discharged cells arc turned off because of the addressing failure. Particularly, the addressing failure at the last scan line is more serious than at the first scan line. The failure is accompanied with delay of the address discharge and reduction of total charge involved. In order to compensate this kind of misfiling, the progressively increasing address voltage waveform is used instead of constant one. In this method, we found that the total charge and address time at the last scan line are similar to those of the first line. As a result, we can have stable discharge without misfiring even at the high ambient temperature.

In this paper, we measured 3-dimensional temporal behavior of the light emitted from discharge cell of plasma display panel(PDP) as a function of the pressure using the scanned point detecting system. The detected light signal through the PM tube is sent on the oscilloscope and oscilloscope which is connected to PC with GPIB. The whole system is controlled by a PC. From the temporal behavior results, we could analyze the discharge behavior of panel with Ne-Xe(4%) mixing gas and 300torr, 400torr, 500torr pressure. The top view of panel shows that the discharge moves from inner edge of cathode electrode to outer cathode electrode forming arc type. At the 300torr, initial emission time is very fast. The side view of panel shows that the light is detected up to $150{\mu}m$ height of barrier rib. In the panel of 300torr, emission distribution is wider than the others.

In order to be good display, the ac PDP lifetime should be guaranteed over 30000 hours. Therefore, to satisfy these demands, it is need to find out main factors in ac PDP affecting the lifetime. In this paper, the characteristics of lifetime as a parameter of the MgO deposition rate conditions is investigated. MgO protective layers is fabricated by E-beam. Before measuring the lifetime we have carefully peformed high temperature evacuation and aging procedure, which is essential for providing the initial condition of our experiment. If MgO deposition rate increased, MgO film becomes dense and an adhesive power of MgO film gets better and because occurrence rate of the MgO cluster decreases, lifetime of MgO will be improved. As a result, ac PDP lifetime can be improved due to the improvement of MgO by MgO preparation conditions.

We proposed the new reset waveform for reducing reset period. The square pulse is applied to the address electrode when the ramp pulse increases before a discharge occurs between sustain electrodes. If the discharge occurs between address electrode and X electrode, the wall charge is reversely accumulated between sustain electrodes compared with the applying voltage before the discharge occurs between sustain electrodes. So the next discharge more weakly occurs between sustain electrodes. If the more weak discharge is obtained, it can make the low background luminance and the high contrast ratio and reduce ramp up time in the ramp reset waveform.

Image sticking, the phenomenon that the previously displayed pattern still remains after the image is changed into different image, is one of the most serious problem in realizing high picture quality. In this paper, we tried characterizing this undesirable feature in terms of the luminance and the intial firing voltage at ramp up time in reset period. It was found that the cell located at the boundary of previous image pattern show low firing voltage and high background luminance. And the results show that the degree of the image sticking is severely affected by discharge duration and the length of the sustain period.

The relationships between MgO deposition conditions and firing voltage of AC PDP were investigated as a function of ambient temperature. Substrate temperature and growth rate were selected as the major parameters that can affect the properties of MgO most significantly. Firing voltages increase with increasing temperature regardless of deposition conditions of the MgO layer. However, the relative magnitude of the firing voltage variation decrease with increasing substrate temperature and decreasing deposition speed. It was also found that the sample obtained at the condition of lower deposition rate shows better dynamic margin characteristics.

Ultra-wide bandwidth (UWB) detection method has been widely used as a front end detection scheme for the ultra-high frequency (UHF) partial discharge (PD) monitoring systems. A broad-band video detector module was developed and characterized for the UHF UWB PD detection systems. The useable bandwidth of the module is more than 2 GHz and it is optimized for 50-ohm systems. The detection sensitivity and dynamic range of the module were characterized by using a known ns-width RF pulses of GHz range. The dynamic range is more than 6-decades and the module can detect pulsed RF signals down to 1 nW. The detector module can eliminate expensive equipment such as high speed oscilloscopes and radio frequency (RF) spectrum analyzers. Therefore, it enables one to use slow speed data acquisition systems for the PD monitoring at the UHF range. The detector module was used to detect real PDs of about <3 pC. The module converts the UWB PD signals into a low-bandwidth video signal with a high signal-to-noise ratio.

The defects making partial discharge(PD) in a C-GIS(Cubicle Insulated Switchgear) initiate acoustic wave which can be detected using acoustic emission sensor placed outside or inside the C-GIS enclosure. In this paper, partial discharge property for 2 locations for AE sensor and 3 locations for defects in C-GIS are presented and PD waveforms were analyzed by PRPDA(Partial Resolved Partial Discharge Analysis). As a result, using post amplifier having gain of 10,000 and band pass filter having $20kHz{\sim}300kHz$, resolution of waveforms AE sensor signal by detected was good. Noise level was about 80 mV.

Ultra-wide bandwidth (UWB), narrow bandwidth (single frequency), and a combination of both technologies have been studied for the ultra-high frequency (UHF) partial discharge (PD) monitoring system as a detection scheme. We have experimentally compared those detection methods using a mock-up of 362 kV class single phase gas-insulated switchgear (GIS) and a stable PD source. A rolling-ball type PD cell that produces PDs of about 10 pC, is placed at one end of the GIS. An internal UHF PD sensor was attached several meters away from the PD source. The PD spectrum was measured up to 3 GHz. A useable bandwidth of more than 1 GHz was used to measure UWB signals from the PD. To simulate the narrow bandwidth scheme a bandwidth of 100 kHz centered at several different frequencies was used.

Up to now, one of the most serious problems in AC PDP is low luminous efficiency. One possible candidate for solving such problem is using high density Xe. But an increase of the Xe percentage cause rising of the driving voltage and so even if brightness is being increased, luminous efficiency is decreased. In this study, to solve this problem, we proposed new electrode structure. A test panel fabricated using new electrode shows an improvement of efficiency by 25% and a lowering of sustain voltage by 20% compared with the conventioned structure.

경제성장과 더불어 신뢰성이 높은 양질의 전기에너지의 공급이 필요하게 되었다. 최근에는 고압 $SF_6$가스를 절연매체로 하는 가스절연개폐기(Gas Insulate Switchgear:GIS)설비가 여러 지역에서 건설 운전 중이다. 본 논문은 GIS내의 $SF_6$가스의 온도변화에 따른 절연특성 및 $SF_6$의 액화에 따른 절연특성에 관한 연구이다.

In this paper, a comparative study of time-frequency distributions by partial discharge(PD) kinds was made. The PD kinds were to be classified into the corona, the surface discharge and the void discharge in this paper. As a result, the distributions of the PD kinds were different, and using neural network, the PD pattern recognizing rate was about 85[%].

Since more than two decades, the conventional PD detecting systems have been employed in order to detect the partial discharges occurring inside the HV power apparatus for their diagnosis by use of different type of detection such as acoustic and UHF detection method. Regardless of their wide on-site application, a certain number of technical inconveniences have been disclosed as follows : multistage amplification. large volume, susceptible to external noise and high price. In this respect, the optical measurement techniques are widely proposed in these days in this concerned field ascribed to the following advantages : immune to external EMI noise and broad band response of the Pockels cell covering from DC to GHz. However, the reliability of several proposed techniques enabling to measure the electric field inside the large high power apparatus has not yet been well approved In this work, an optical measuring system, based on the Pockels effect, has been developed for measuring the field variation due to the corona discharges occurring in air and in oil. This system consists of He-Ne laser, single mode optical fiber, multi mode optical fiber, polarizing film, Y-cut LiNbO3 cell, photo detector, digital oscilloscope and personal computer with GPIB. For this purpose, optical probe has been specially designed and realized and put into the needle-plane electrode. Afterward, same measurement is carried out in oil. We demonstrate the characteristic of the optical measuring system and the measurement results.

자장 크기 변화에 따른 마이크로파를 발생시켜 출력 크기를 측정함에 있어 축 방향 자장의 크기를 두가지 크기로 변화시켜 결과 자장크기 부근에서 출력증대가 일어났다. 이는 전자 사이크로트론 공명에 의한 출력증대로 볼 수 있으며 수직방향의 크기로 간주된다. 본 실험에서는 원래 수평방향의 자계에 대하여 출력발생 및 출력증대가 이루어지는 후진파 발진기를 이용한 실험을 하였다. 주파수 18${\sim}$21GHz대를 이용하여 측정한 결과 0.3T와 0.7T부근에서 출력증대 및 효율증대가 이루어 지는 것을 관찰하였다.

In this paper, High Frequency PD measuring system using directional coupler sensors(DCS) is introduced. Especially the principles of the DCS and characteristics of the system are introduced. Evaluation of this system was carried by an adoption to the test circuit of 345kV XLPE $2000mm^2$ cable and EB-A, EB-G, PIJ, PNJ. In the test a PD measurement was carried out without shieldroom and under the on-line state and in the high frequency range at the remote site from the test object. The test result was satisfactory and this is due to the use of DCS and using a high frequency range and specific filter for radio and TV signal and low pass. This system can be used to the test of a new construction of cable and accessories and measuring of long-term deterioration of cable and accessories. And this will bring us the reliability of a power transmission.

A computational approach of the arc quenching process in GCB was developed. it is capable to calculates the thermodynamic quantities of the gas as a function of time taking into account of all spaces concerned with the arc quenching. Basically using so-called FLIC method, this program adoptes 'Simplified Enthalpy Arc Model', which is somewhat modified. And, to examine whether our works were done properly, it was simulated the whole process of the arc quenching that is based on self-flow generation phenomena/current interruption in a thermal expansion type circuit breaker. This program was verified by experiments, both showed fairly good agreement.

현재 국내에서 많이 연구 개발되고 있는 펼스코로나 방식은 자동차와 같은 소규모 오염 배출 원에 적용하기엔 경제적.기술적 한계를 가지고 있으며, 또한 3원 촉매법과 같은 화학촉매환원법은 사용조건이 엄격하고 일부 오염물질의 저감만이 가능하기 때문에 종합적인 공해물질 저감대책으로서는 한계가 있다. 따라서 자동차와 같은 소규모 오염배출원에 있어서 다양한 배기오염물질의 동시처리가 가능한 경제적이고 종합적인 공해물질 저감방법의 제시는 매우 중요한 당면 과제이다. 이에 따라 본 연구에서는 현재 본 연구팀이 보유한 전기재료 및 방전분석 기술을 바탕으로 최근 국외에서 자동차 배기가스에서 공해물질의 배출억제 방안으로 활발히 연구되고 있는 유전체방벽방전 방식에 대해 체계적 실험 분석 등을 통하여 보다 효율적인 공해물질 제거방법을 도출하고자 한다.

High voltage(H.V.) induction motors have been applied to various industrial applications. But aging and failure of induction motors are initiated by electrical, mechanical, thermal and chemical processes during manufacturing or in-service. These detects reduce locally the dielectric strength of the insulation. At such defects partial discharges can occur, which cause further degradation of the insulation and reduce the life time of the H.V induction motors. Consequently in this paper, we studied the partial discharge pattern analysis of H.V. induction motor for on-site applications.

The unpredictable threat of lightning surge is ever increasing in today's low-voltage power supplies. Thus Surge protection devices for AC mains are more widely used. The false-tripping of the earth leakage breaker (ELB) can be caused by the installation of surge protection devices with MOV. In order to examine the cause of malfunction, the malfunction characteristics of ELBs applied by lightning surge were investigated experimentally. As a result, all of them brought about malfunctions under 7 kV of the impulse voltage. The suitable position of MOV and use of zener diode were suggested to eliminate the problems.

Acoustic partial discharge detection has been used on GIS testing for more than 10 years. Sensitivities show that most of critical defect types can be detected with a reasonable signal-to-noise ratio. The paper reports on acoustic partial discharge detection comparable to sensitive electrical PD(partial discharge) measuring method.

KEPCO is planing to adopt a preventive diagnostic system to obtain the reliability of transformer and GIS in 765kV substation. KEPRI has developed the preventive diagnostic system for 765kV substation since 1997. We used various sensors and fault detecting devices such as a dissolved gas analyzer in oil, a ultrasonic detector and LA leakage current detector, etc., and carried out adaptation tests at the both a laboratory and a site. We developed a data acquisition system, a communication control unit and a server system as well. Furthermore, monitoring program and diagnostic expert system were also developed. This paper describes the preventive diagnostic system for 765kV Sin-Ga-Pyong and Sin-Tae-Baek substations which will be operated from 2004.

Recently, the HFPD measurement methods that detect high frequency bandwidth of frequency components of partial discharge pulses are proposed and many studies are carried out. The HFPD measurement method is able to detect partial discharge signal in active line, therefore this method has a merit that can does condition monitoring of power equipments and measure growth state of partial discharge erosion with on-line and real time. In this study, the radiated HFPD signals are detected by antenna and aging diagnosis is executed with a neural network algorithm. As a result of this study, the aging diagnosis of insulation material using neural networks is possible.

This paper introduces a on-line monitoring system for insulation diagnosis of high-voltage motor stator windings. This system monitors the insulation condition of the stator winding with sensor, coupling capacitor. Partial discharge (PD) signals are able to be continuously measured and digitalized with a Peak-hold A/D converter to build the database of the high-voltage motor's insulation condition. This system can communicate with the central monitoring system via RS-485 This paper introduces an economic solution for data acquisition of partial discharges.

With increasement of use in electricity energy, quality of electric apparatus has been recognized as important factor in distribution and transmission line. Especially In laboratories, lightning and switching impulse performances of electric apparatus have been carrying out by impulse voltage generator (IVG), simulated into lightning and switching surge circuit. In this paper, we describe triggering system of impulse voltage generator(IVG) for extra high voltage, which has been newly designed.

Ionic wind may be produced by DC corona discharges. In this work, the electrical effect has studied to evaluate applicability in fields of electrostatic cooling, ozone generation, electrostatic precipitation, heat transfer, air flow modification, and etc. The ionic wind velocity was measured as a function of the distance of pin to plate and the diameter of punched hole. The pin to punched-plate electrode generates airflow from pin to plate and the flow direction is controlled by the hole size of punched-plate, input voltage and distance between two electrodes. As a consequence, the ionic wind velocity is nearly proportional to the applied voltages and ranges from 1 to 3 m/sec.

Recently, the pulsed power system has been used to many applications. Such as remediation of environmental hazards, food sterilization, air pollution control E/P (Electrostatic Precipitator), DeNOx/DeSOx power system, ozone generator, high energy physics, and other power source applications. A pulse energy efficiency for load depends on the rising time, peak value. Pulse duration and impedance matching etc. The pulsed power system generally required for short pulse duration and high peak value was forced to consider its volume and economy. In this paper, we investigated operating characteristics of the CO2 laser using an inductively pulsed power system.

Optical fiber sensor is a subject which has been attracted considerable attention in recent year. Especially, it is being developed for the detection and location of partial discharge in oil-filled transformers. In this paper, we propose and experimentally demonstrate directivity and sensitivity of a hollow cylindrical mandrel sensor. The sound source is a PZT actuator of hollow cylinder type. Several layers of the fiber laminated around the mandrel surface and experiments were performed on three axis modes. The experimental results can be applied to analyze detected signals optimally.

Electrodeless discharge lamps have been objects of interest and research for several decades, mainly because of their potential for extremely long life, high lamp efficacies and smaller than standard fluorescent lamps size. A series of measurements and observations concerning variables has yielded optical and electrical characteristics for electrodeless discharge lamp like incandescent lamp and circular lamp feature. Last experiment were carried out to determine the lamp temperature at several surface points during operation. Light output levels in excess over 60,000 cd/$m^2$ have been measured in electrodeless discharge lamp for a general of conditions. At lamp surface temperatures have been measured over $80^{\circ}C$, and starting current have been measured over ${\sim}A$.

This paper deals with the analysis of field condition for earth leakage current alarming system in the stage lighting, stage sound stage machinery installation. These analyses of field condition were carried out in accordance with investigating an installation of earth leakage current alarming system with respect to a main line of power source, dimmer, sound equipment, machinery mobile unit equipment and so on. As a result of analyses. The earth leakage current alarming system has been installed only a part of the main line of power source and the probability of places which were installed was less than 50(%). Therefore, it is desirable that the earth leakage current alarming system is installed at places which are suitable, for example, dimmer, each kind machinery etc. in order to prevent electrical hazard.

A novel ozonizer has been developed using a high-frequency surface discharge and a high purity alumina ceramic as its dielectric component. A thin ceramic layer, cylindrical in form, is adhered by a film-like induction electrode. An ac exciting voltage of frequency to 0.6 kHz from 1.0 kHz and $6{\sim}9kV$ peak-to-peak is applied between the electrodes to produce a stable high-frequency silent discharge for generation of ozone. A substantial reduction of the exciting voltage is also enabled by using a thin alumina ceramic layer. As a result, the ozonizer can easily produce ozone concentration($128g/m^2$ for oxygen) and power efficiency(360g/kWh for oxygen) without using a special enrichment means.

To cope with increasing of electric power demand in metropolitan areas, large capacity underground power cables are needed. Under such situations, our company has developed 345kV XLPE insulated cable and accessories. As the final step of development of the 345kV XLPE cable and accessories, the pre-qualification test was carried out on the test line composed of cables, pre-fabricated joints, EB-Gs and EB-As. This paper sums up the pre-qualification test conditions and the results.

This paper proposes a multi-color lamp using ROB LEDs for color variation. The lamp has an internal controller circuit. so it can be directly connected to the existing incandescent lamp socket. It's main body is comprised of two PCB layers. The upper layer contains 44 LEDs and the lower one has a simple microcontroller-based PWM control circuit. Appropriate number of RGB LEDs are so chosen according to the color mixing theory that the overall LEDs represent a color temperature of 6500K. The lamp has functions of both ON/OFF control and PWM control, so is capable of color variation of over 100,000 colors and of more than 10 patterns.

The important parameters deciding the fluctuation of laser beam are smoothing capacitor, frequency and the characteristics of laser resonator. In this thesis, we control the fluctuation of $CO_2$ laser in realtime by changing Duty-Ratio of IGBT and switching frequency with fixed the smoothing capacitor to improve the fluctuation of laser beam. We detect the light on laser resonator using a CdS photo sensor to improve ripple factor of laser beam and feedback fluctuated signals refined by a band pass filter into the control circuit to stabilize fluctuation actively. There is much to be desired in the realtime controlling technique of the light on laser discharge tube in electrical signal. We propose switching control technique with microprocessor and photo sensing technique by controlling switch devices optimum operation and feedback signals detected by a photo sensor into the laser power supply in order to improve ripple factor of the $CO_2$ laser beam.

Oil-filled power cables and XLPE power cables have been globally applied for extra-high-voltage underground power transmission lines. The application of XLPE cables for the transmission lines have been largely increased at the domestic and overseas projects because of some issues. O.F cables have some week points, related with the issues of the environmental pollution and the needed maintenance work, even though they have been applied for several ten years and their reliability has been proven. Meanwhile, the demands on XLPE power cables increase as their manufacturing technologies have been improved and their simplicity of installations has been focused on. In Korea, for the first time, the 275kV XLPE cable is to be applied at an overseas power plant project. This paper introduces the project profile, the design of the XLPE cable and its accessories, the cable system design and the installation design.

본 논문에서는 현재 당사에서 GIS 제조업체로서 당사의 제품에 대한 예방진단 시스템을 구축한다는 계획의 일환으로서 진행하고 있는 신가평/신태백 765kV 변전소의 800kV/362kV GIS용 피뢰기 누설전류 측정장치 개발에 대한 전반적인 개요와 진행 상황에 대해서 기술하도록 한다. 우선, 피뢰기의 일반적인 열화 특성에 관해서 고찰하며, 개발된 피뢰기 누설전류측정장치의 시스템 구성도를 통해서 미소전류에 대한 신호처리기법을 소개한다. 또한, 본 장치를 개발함에 있어서 진행된 전자기 적합성(Electromagnetic Compatibility) 시험 및 절연 내력 시험에 대해서 서술하며, 시험 전, 후의 입 출력 특성을 확인함으로서 제품의 신뢰성을 검증하도록 하였다.

This paper described the outputs of acoustic sensors due to the vibration of particles in the mock up GIS. We used the two type of acoustic sensors which had 150kHz resonant frequency and 60kHz resonant frequency respectively. In the experiment of the mock up GIS, we paid attention to the relationship between outputs of sensors and particles and we found that the ratios of outputs related with the lengths of particles. We developed the apparatus including the above diagnosis algorithm for GIS.

This paper describes the effect of secondary surges entering low voltage side on the primary winding of pole transformers. After having connected the secondary winding by 4 different methods, surge voltages were applied to the low voltage side, and voltage waveforms were measured at a surge applied point and a high voltage bushing terminal. The measured voltages were compared by the waveform, magnitude and damping characteristics with each connection. As a result, the voltage waveforms induced by the secondary surges were different one another with each connection, especially, the conventional connecting method for 2 voltage sources was far different from the present method supplying only 1 voltage source in shape of the voltage waveform.

Partial discharge is attendant physical phenomenon on electromagnetic, sounds, lightning and mechanical vibration. In this paper, we simulated GIS and measured the radiated electromagnetic wave emitted from partial discharge in $SF_6$ gas using antenna(30[MHz] ${\sim}$ 2[GHz]) and spectrum analyzer. This paper describes characteristics of radiated electromagnetic waves with distance 1 [m] between antenna and discharge source.

Arc phenomena occur in the air, must be more diverse than vacuum and SF6. An air arc interruption method has been used in low rated voltage circuit breakers such as ACB, MCCB and MCB. Most of them have the arc chamber composed of arc chutes and lateral walls that made of many kinds of materials. Therefore, the criterion of material selection is necessary for breaking capacity improvement. So, we selected some contact and lateral wall materials, and carried out short circuit tests. Especially, some parameters of arc plasma properties were very different each polymeric wall material.

This paper deals with an effective installation method of lightning protective devices for information and communication facilities. Due to the potential difference between grounding of the AC power lines and communication lines, the equipments connected to the communication lines are easily damaged by lightning surges. So we have examined the behaviors of surge protective devices against lightning surges from the AC power lines and signal lines, and the coordination effects of SPD installation method were investigated. As a result, it was confirmed that the bypass arrester method and common grounding method were very effected.

Global simulator for $CF_4$ discharge in transformer coupled plasma (TCP) source is developed and simulations arc performed under various conditions. The developed simulator is based on a set of space averaged fluid equations for electrons, positive ions, neutrals and radicals of $CF_4$ plasma. And the used absorbed power by electrons is calculated by a 2-dimensional heating model[1].

In this work we develop an equivalent circuit model of TCP(transformer coupled plasma) source and investigate matching characteristic. The developed circuit model includes transmission line, standard-type impedance matching network and displacement current in the plasma source. The impedance of TCP is calculated by previously developed program for various source parameters and dependance of components of matching impedance on the value of source impedance is investigated.

A silent discharge type ozone generator using a water surface as an electrode has been proposed and investigated experimentally. A water surface has many Taylor cones when the ac voltage is applied on its surface, which increase the discharge surface greatly. In this paper, it was studied about the effect of the water conductivity. As increasing the water conductivity, the amount of generated ozone was increased and the silent discharge on the water surface took place steadily and calmly.

The current density in the IPS(Inverse Pinch Switch) is 1/62 times less than that in the spark gap. It was shown that in comparison with the spark gap, the switch inductance of the IPS is largely reduced and the useful lifetime is significantly increased. In the paper, the design technology of a closing switch, especially IPS triggered by electrical signal for pulsed power system with a very high voltage and current is presented.

정전형 펄스파워시스템에서 핵심은 투입 스위치라고 해도 과언이 아니다. 이러한 투입 스위치 중 진공 아크를 이용하는 스위치로는 로렌츠력을 이용 아크를 회전시켜 전극의 손상을 억제한 횡자계형과 전극의 축방향으로 자계를 발생시켜 아크가 확산되도록 함으로써 z-pinch에 의한 전극 손상을 감소시키는 종자계형으로 대별 할 수 있다. 본 논문에서는 고전압/대전류용 횡자계형과 종자계형 진공스위치의 동작특성을 파악하기위해 아크전압-전류 특성에 대해서 기술하였다. 횡자계형 전극과 종자계형 전극을 동크롬(75:25 [wt%])으로 제작하여 진공 챔버 내에서 실험을 통해 아크 전압과 전류를 측정하였으며, 이를 통해 아크 저항과 손실 전력을 구하였다.

Because the overhead transmission lines are exposed to the outdoor weather, the faults of the transmission lines are due to natural conditions, and among these faults, the outage rate by lightning is about 50%. The lightning causes the damage of power system equipments, the shut down of electricity and the electro-magnetic interference. To study the basic research of the lightning parameters for power system operation, LPATS-III (Lightning Positioning and Tracking System) has been introduced since 1995 in Korea. This paper describes the inspection result about location information error and the statistical distribution of lightning current.

무성방전을 이용한 오존발생기에서 오존생성에 영향을 미치는 인자로는 원료가스의 온도, 습도, 유량, 방전전극의 재질과 형태, 전원의 형태 등 다양하다. 본 연구에서는 전극의 면적변화에 의한 오존생성특성을 살펴보았다. 그 결과, 방전전극의 면적이 넓어짐에 따라 더 많은 전력의 인가가 가능하여 대용량의 오존발생기의 제작이 가능하며, 또한, 동일한 전력을 인가하는 경우에도 전극면적의 증대가 오존발생특성의 향상을 가져옴을 알 수 있었다.

본 연구에서는 대기압 교류방전시 비열플라즈마를 이용하였을 때 NO입자의 분광스펙트럼과 전극재질과 전극두께에 따른 신호강도를 측정하였다. 분광기를 이용하여 측정된 NO입자의 분광스펙트럼 분포를 바탕으로 측정된 파장대역 중에서 비교적 신호강도가 큰 파장대역인 226[nm], 236[nm], 247[nm], 259[nm]에서 전극의 재질을 스테인레스, 구리, 알루미늄으로 변화시켰을 때의 신호강도와 전극의 두께를 4[mm], 5[mm], 6[mm]로 변화시켰을 때의 신호강도를 분광기(Monochromator)를 이용하여 측정하였다. 또한, 측정대상 중 전극재질은 구리일때가 가장 신호강도가 높음을 확인할 수 있었으며 전극두께는 갭 간격이 작을수록 신호강도가 강한 것을 확인함으로써 NO입자의 방전 메카니즘을 보다 명확하게 규명하고 또한 방전 리액터 제작에도 좋은 자료를 제공할 수 있을 것으로 생각된다.

In this paper, the coefficient of friction betwee and sheath in 345kv XLPE cable was measured the simulated inclinated condition of You-Youngdeungpo transmission line. The phenomena of slipping down the simu inclination was investigated theoretically usin measured data and was analyzed from experim result. The measured and analyzed result were conside be as a reference data for real installation of XLPE Youngseo-Youngdeungpo transmission line.

폐수에서 발생하는 슬러지(Sluge)의 효과적인 처리를 위한 전기적 충격파를 발생시키는 장치로 고전압 펄스 전원 시스템을 제작하였다. 제작한 고전압 펄스 전원 시스템의 제원은 최대 출력 전압 60 kV, 최대 반복 주파수 500 Hz 이며, 한 펄스 당 최대 출력 에너지는 20 J 이다.

In this paper, we describe the development in joint and termination for 230kV oil-filled cable. The designed accessories are based on the results of electric field analysis by electrostatics theory and FEM.

Conventional current transformers possess many qualities due their simplicity. However, the technological innovations now underway in the field of switchgear and substation control systems tends to underline their drawbacks. New technologies must be developed to provide users with better service quality in terms of precision, operating safety and interoperability. The current transformer presented combines simplicity and the high degree of precision offered by Rogowski coils with the processing possibilities of digital electronics.

$SF_6$ 가스로 절연되는 GIS (Gas Insulated Switchgear)는 매우 우수한 신뢰성을 확보하고 있지만 사고 발생 시 파급효과가 매우 크므로 상시 감시할 수 있는 진단기술이 요구된다. 본 논문에서는 GIS 내부에서 발생하는 신호를 검출하기 위해서 전기적인 방법과 비전기적인 측정 법을 통해 전자파. 초음파, 전류펄스를 측정하고 비교하였다. GIS 내부알루미늄도체에 침 결함을 고정시켜 전원전압 인가 시 발생되는 부분방전신호를 UHF, AE, CT센서로 검출하였다. 측정 결과 UHF센서와 CT센서로 검출되어진 신호는 매우 유사하게 측정되었고 초음파와 전자파를 검출한 결과 진행속도 차이로 발생되는 시간지연현상이 발생되었다. GIS내 부분방전발생 시 발생되는 전자파 스펙트럼 분석결과도 650MHz에서부터 935MHz까지의 주파수대역이 측정되었다. 이후에는 현장에서 운전중인 GIS내부에서 발생되는 결함들을 실제와 가깝게 모델링하여 발생되는 부분방전신호를 스펙트럼 분석하여 대역에 맞는 UHF센서 개발에 노력하고자 한다. 또한 결함의 종류와 형태에 따라 다르게 발생되는 부분방전신호를 검출하여 측정하고 이를 진단하는 연구가 계속 진행되어야 할 것으로 사료된다.

The pulsed power system was widely making use good of many industrial and environments. The pulse generator generally required for short pulse duration and high peak value was forced to consider its volume and economy. In this paper, this system is designed and fabricated which has a compact size of pulse generator with switched MOSFET. We have studied the removal of rust material using Arc discharging in pulsed power system. It have tested their characteristics by adjusting variable voltage charging and pulse repetition rate. As a result, We can eliminate rust materials with this device.

KEPCO has a plan to operate 765kV electric power network from June, 2001, by the KEPCO's plan. We have developed the extra-high voltage class equipments for 765kV substation. Inpecial, we have proceeded the developments of 800kV Gas Insulated Switchgear from January 1998 to now. Until now we completed the test of a general characteric tests of GIS, the short-circuit test of GCB. DS. ES. HSGS.

In this study, asolid-state laser system adopting a firing time control(FTC) method in which three flashlamps are turned on consecutively was designed and fabricated to examine the pulse width and the pulse shape of the laser beams depending upon the changes in the lamp turn-on time. That is, this study shows a technology that makes it possible to make various pulse shapes by turning on three flashlamps consecutively on a real-time basis with the aid of a PIC one-chip microprocessor With this technique, the lamp turn-on delay time can be varied more diversely from 0 to 10 ms and the real-time control is possible with an external keyboard enabling various pulse shapes. In addition longer pulses can be more widely used for industrial processing and lots of medical purposes.

This test was performed to assess the insulation deterioration condition of the stator winding of Chung-Ju hydrogenerator #4 and Dae-Cheong hydrogenerator #2 which had been in service after being constructed 1980. The insulation diagnostic tests include resistance polarization index(P.I.) AC current, dissipation factor(Tan ${\delta}$) and partial discharges ($Q_{max}$). The results of diagnostic tests were compared to factory test measurements.

As the statistical data, the electrical shock accidents by electrical power facilities of 22.9kV substation is about 100 per years which shows very high occupation rate of 11.3%. There is many hazard factors in this place using high voltage because electrical accident can be occurred in near live part as well as contact. Regarding electrical shock accident in 22.9kV substation as there are many cases that have not been exposed industrial disaster, it is very hard to know exact causes of such accidents in many cases, and therefore it is difficult to set up effective preventive measures. Therefore in this paper, it is intended to prepare the basic data to establish more effective preventive measures of electric shock accidents in 22.9kV substation through understanding the real conditions based on investigation and analysis in various types.

Nowadays, CO2 lasers are used widely in many applications such as materials fabrication, communications, remote sensing and military purpose etc. It is important to control the laser output power in those fields. In this paper, current resonant half-bridge inverter and Cockcraft-Walton circuit are used to vary the laser output power. This laser power supply is designed and fabricated which has less switching losses and compact size. Also we used an IGBT(Insulated Gate Bipolar Transistor) as a switching device of a power supply and PIC one-chip microprocessor are used to control the gate signal of the IGBT precisely. We investigated the output characteristics of this CO2 laser. As a result, the maximum laser output power of 26[W] is obtained at the resonant frequency of about 13[kHz].

본 논문에서는 반도체 제조공정에서 발생하는 $CF_4$의 분해와 제거를 위하여 3상 교류 플라즈마 토치를 제작하고, 플라즈마를 발생시켜 $CF_4$제거 가능성과 이에 따른 문제점에 대해 알아보았다. 매우 강하고 안정한 C-F 결합을 깨고 $CF_4$가스를 분해하기 위해서는 1100[$^{\circ}C$]정도의 고온이 필요한데, 본 실험의 플라즈마 플레임의 경우 $CF_4$가스를 열분해 광분해 시키기에는 충분한 온도와 에너지를 가지고 있다고 사료된다. 하지만 고온의 플라즈마와 토치 내부의 복잡한 유동과 고온의 플라즈마에 의한 전극의 융삭문제는 플라즈마를 연속적으로 발생시켜 $CF_4$가스의 제거효율을 높이기 위해서는 필히 개선해야 할 문제점인 것으로 사료된다.

The purpose of this experiment was to develope Triggered Vacuum Switch (TVS) for the high voltage and high current. The TVS has an array of rods of alternate polarity in which a fixed gap spacing is maintained between the rods. The cross section of each rod has trapezoidal shape. It consists of electrode, ceramic chamber, getter and trigger. Currently, triggered vacuum switch (TVS) with seal-off has been designed and fabricated at PAL. An experimentation and trigger devices for TVS were designed for testing characteristics of electricity. For making the prototype of TVS, it is developed of fabrication process and fined of electrode material. The fabrication of the TVS is a lot of process which have manufacturing of part, chemical clean, ceramic brazing and metal welding. The fabricated TVS is tested of leak for vacuum, hold-off voltage and conditioning of trigger system. The TVS has pinch-off after it is removed of gas in the TVS and activated of getter in degassing furnace. The prototype TVS tested about 20 kV, 75 kA, 83 ${\mu}s$ with 100 kJ capacitor bank and inductance 5 ${\mu}H$. This paper describes the results of tests and the characteristics of the switch.

This paper describes AC test for long delivered drum length of cable using pre-breakdown partial discharge detection(PPD) method, which can be applied to observe the causes of electrical breakdown of EHV XLPE insulation. This method is to de-energize applied voltage to cable rapidly using pre-breakdown partial discharge, and is able to prevent complete breakdown. By this effect, defects such as voids, metal particles and protrusion in cable can be observed clearly. AC resonant test set was used for PPD method. Localization of partial discharge was performed by time difference detection of the traveling wave. Accuracy of localization was 1% to the length of test cable. Through several experiments with XLPE cable, successful results of PPD method were obtained.

We measured 3-dimensional temporal behavior of the light emitted from AC plasma display panel(PDP) at various auxiliary voltage pulse width supplied to the address electrode in sustain period using scanned point detecting system. In the case of applying an auxiliary address voltage pulse, the light emission starts at the inner edges of the cathode so the larger discharge volume toward address electrode can be obtained compared with the normal sustain discharge. Especially, when the auxiliary voltage pulse width is the $2{\mu}s$, the maximum luminance and long emission time can be obtained.

UHF 부분방전시스템은 GIS 내부에서 발생하는 절연이상을 가장 효과적으로 검출해 낼 수 있는 방법이지만, 기존의 IEC60270법에 의해 측정된 겉보기 방전량과는 직접적인 상관관계를 가지지 않는다. 현재 신가평과 신태백의 765kV 변전소에 설치되는 800kV GIS는 제작자가 부분방전센서를 취부하여 납품하여야 한다. 본 논문에서는 한전규격을 만족할 수 있는 센서의 감도시험법에 대하여 고찰하였다.

본 논문은 패러데이 효과(Faraday Effect)에 의한 초고압 전력설비에서의 광CT 특성에 대한 기초 연구를 기술하였다. 광원은 LD(Laser Diode : 830[nm])를 사용하고, 수신부는 PIN-Photodiode론 사용하였다. 광의 전송로는 파이버 내에서 편광상태론 유지할 수 있는 싱글모드 광파이버를 사용하였고, 광파이버의 양끝은 편광자와 검광자를 두어 빛의 광학적인 편파면을 이용한 전류측정이 가능함을 확인할 수 있었다. 측정 결과에서는 기존 문헌상의 결과와 동일한 형태의 출력을 얻을 수 있었고 나아가서는 초고압전력설비인 가스절연개폐장치 (GIS: Gas Insulated Switchgear)에 대한 적용도 가능하게 했다.

고전압 대 전류를 필요로 하는 펄스 파워 시스템에서 스위치는 중요한 소자중의 하나이다. 펄스 트랜스포머를 이용하여 고전압 펄스를 만드는 회로에서 대전류 스위칭에는 대부분 스파크 갭 스위치나 싸이라트론을 사용하는데 높은 펄스 반복 율과 긴 수명을 제공하기 위해서는 반도체 스위치를 사용해야한다. 고전압 대전류 펄스파워 시스템에 적합한 반도체 스위치의 스위칭 특성과 제어방식에 관한 연구를 수행하였다 실험에 사용한 스위치는 20 kV, 12.6 kA, 12 ${\mu}s$의 펄스 스위칭이 가능한 ABB사의 반도체스위치 스택 (5SPR-26L4508-8-WC)이다. 실험회로는 콘덴서에 충전을 완료한 다음 스위치와 인덕터를 통하여 방전하도록 구성하였다. 8개의 직렬 연결된 스위치는 광케이블을 사용하여 병렬구동하고, 고주파 스위칭 전류전원을 사용하여 고전압 절연을 하면서 게이트 구동전력을 전달하도록 하였다. 본 논문에서는 스위치 전압과 방전전류를 관측하여 반도체 스위치의 특성을 조사하였다.

유입식변압기 내부고장의 조기발견을 위하여 유중가스분석법이 가장 일반적으로 사용되고 있다. 본 연구에서는 변압기 내부이상의 종류에 따른 발생가스의 특성과 유중가스분석법으로 사용되고 있는 key gas법 Donenburg법, Rosers법, IEC법에 대한 특성을 비교분석하였다. 동일한 가스성분에 의해서도 각 진단법이 의한 진단결과가 다르고, 또한 진단결과가 발생하지 않는 경우가 발생하고 있으며, 고장원인이 2가지 이상으로 복합되어 있는 경우 모든 고장원인을 밝혀낼 수 없는 것으로 나타났다.

A shorted-turn test was performed at the Sininchon combined cycle power plant on gas turbine generators. The test was conducted using a permanent flux probe and on-line diagnosis system. The flux probe installed in the generator air gap senses the field winding slot leakage flux and produces a voltage proportional to the rate of change of the flux. This pattern of flux variation is a signature unique to each field winding. We have also applied a voltage waveform analysis technique that can identify the pole location, slot number and number of shorted-turn with each slot.

In this paper, we studies EMTP analysis and characteristics of critical voltage of pulse corona and load impedance on variable electrode length. To obtain a stable Pulse voltage, we designed a compact pulse generator switched MOSFET and tested their characteristics by adjusting electrode length and pulse repetition. As a result, critical voltage of pulse corona and load impedance on increasing electrode length were decreased. These results indicate we can control critical voltage of pulse corona and suppress arc discharging between two electrodes.

A pulsed Nd:YAG laser is used widely in many applications such as materials processing, communications, military and medical instruments. It is important to control the laser energy in those fields with using a pulsed Nd:YAG laser. In this paper, constant-frequency current resonant half-bridge inverter and feedback control circuit are used to have output stable. This laser power supply is designed and fabri which was isolated. Also, this study is used an one-chip microprocessor, SCR, current transform A stable output of this Nd:YAG laser system investigated. The tested results are described.

As the statistical data, the most of electrical shock accidents have been caused by human errors including those of mistake, carelessness, and so on during normal condition. But, there are currently no international standards for the determination of withstand distance to ensure safety of personnel form 22.9 kV electrical power facilities during their normal operation. Therefore, this paper describes the characteristics of flash-over voltage by moisture variation to establish the distance clearances in terms of electrical safety.

This paper attempts to discuss the pseudo-spark which is developed for high voltage and high current. The pseudo-spark switch is on the basic of the Paschen's law. The pseudo-spark switch fabricates the glass chamber. The pseudo-spark switch consists of hollow cathode, hollow anode, and trigger. The pseudo-spark switch is operated at the voltage of 20 kV and the pressure range of $20{\sim}80$ mtorr with He-gas. The switching current of the pseudo-spark switch was measured as 65 kA, and the duration of the pulse was about 100 ${\mu}s$. This paper describes the results of tests and the characteristics of the switch.

In this study, micro-ohm shunts with rated ac current of 2, 20, 80kA intended for use as an approved system for ac current measurement were calibrated according to IEC 60060. The scale factor and linearity were determined by comparison with the reference measuring system. Measurements of temperature rise due to the rated current was also investigated to analyze a temperature effect. One of the main goals was the determination of the measurement uncertainty of the shunt. The expanded uncertainty of the scale factor for the complete measuring system was satisfied with the STL(Short-circuit Testing Liaison) guide recognized tentatively.

In this paper, frequency spectra of AE signals detected from respective the insulation deterioration were analysed to under ac high-voltage application using epoxy resin sample and insulation oil. Also, frequency spectra of AE signals generated from the load currents in the actual operating transformer of 500[kVA] under distribution system of 22.9[kVJ] were also analysed to distinguish the AE signals due to void discharges from the magnetic circuit noises in transformer. As the experimental results, we could distinguish the AE signals whether those signals were caused due to the void discharges or due to the magnetic circuit noises by analyzing the frequency spectrum of AE signals.

최근 고전압/대전류 펄스파워응용이 점차 늘어나고 있다. 정전형 고전압/대전류용 펄스파워전원장치의 핵심인 폐스위치의 수요 또한 점차 증가 할 것으로 추정된다. 펄스파워전원장치의 안정적이고 신뢰성 있는 동작을 위해서는 주위 조건에 영향을 받지 않는 진공 스위치가 적합하다. 진공펌프, 챔버없이 사용이 간편하도록 sealed-off화되어야 한다. 본 논문에서는 챔버내에서 동작이 확인된 회전 아크형 진공 스위치를 유지전압 22[kV]. 첨두전류 150[kAp]의 사양으로 스위치를 sealed off 제작 및 이를 동작 시험한 결과에 대해 기술하였다.

Partial Discharge is radiated in the form of electromagnetic wave from variable sources. It can be taken by UHF antenna and the signal pulse from that has a nonstationary time-series which can be evaluated with several methods. One of them is STFT(short time fourier transform) processed in frequency region. Statistical results using STFT show the possibility being able to discriminate between several PD sources.

The ramp waveform has recently been introduced to erase wall charges for AC PDP. However, it is difficult to erase completely the wall charges in all cases In this paper, new erase waveform having adaptive erasing characteristics are investigated. The erase margin of suggested waveform is wider than that of the conventional waveform. Moreover, suggested waveform can reduce the erase time significantly.

In this paper, electromagnetic waves radiated from discharge at three-type electrodes (needle-plane, plane-plane and sphere-plane electrode) using DC power source in air measured and the peculiar patterns of their spectra are reported. The radiated electrodmagnetic waves were measured in bandwidth of VHF($30{\sim}230$[MHz]) using a biconcal antenna and a spectrum analyzer. Frequency spectrum distribution of radiated electromagnetic wave was revealed under 50[MHz] at positive DC, and high electric field was shown at 45[MHz] frequency band. But, it was revealed under 70[MHz] frequency band at negative DC under plane-plane electrodes and sphere-plane electrodes, and high electric field was shown at 55 [MHz] frequency band.

Recently, 345kV XLPE Cable and Accessories have been developed and will be applied for Youngseo$\sim$Youngdeungpo project in Korea. So, let this project and the process of development introduce on this paper. The cable type and length of this project is 345kv XLPE 1C*$2000mm^2$ 66km and all cable will be pulled on cable tunnel. The diameter of cable insulation was designed as 27mm, we could reduce it by appling for hi-tech and super-clean system. Joints were developed by a pre-fabricated type which considered high safety and economic issues. We had also done Pre-Qualification test for verifying the reliance of cable and accessories before construction. As we developed this 345kV XLPE cable system including its accessories at the same time, we can have higher technologies and contribute safe power in transmission lines. In adtionally, we can have a stable status for suppling EHV cable systems to a variety foreign customers by ourselves.

At present, the variable sensors are applied to detect PD pulse signals, UHF sensor, AE sensor and etc. In this paper we used the Rogowski sensor to detect PD pulse signals in air. We did performed test simulation and niddle to plane electrode structure for PD source. We compared Rogowski sensor with conventional type PD detector to detect discharge signals in air.

One of the most frequent sources of the accident is metal contaminant in GIS. This paper deals with the characteristics of breakdown voltage of metallic particles using electrodes of various epoxy coating thickness. As experimental results, breakdown voltage of the thickly coated electrode is higher than that of thinly coated electrode. It is considered that resistance of the epoxy coating impedes the development of pre-discharges in the gas.

The technology of sulfur lamps that has physical and electrical characteristics comparable to current HID source has been reported. The fundamental principles of the operation of microwave discharges that are used to convert microwave energy to broad spectrum visual light are known. In this paper, emission dependance of microwave discharges in mixture content of sulfur with noble gases was studied. It is shown that the excitation of this gaseous mixture is carried out in two phases: (l) ionization of noble gas atoms by a microwave field and (2) the consequent maintenance of slightly ionized nonequilibrium plasma by the field. These two processes have essentially various thresholds for the microwave pump. The purpose of this work is to investigate spectral properties of the high frequency discharges in a mixture sulfur vapors with noble gases.

$50{\sim}100$ micron의 지름을 가지는 면광원용 마이크로 할로우캐소드형 태의 플라즈마광 어레이가 2인치 미만의 크기로 제작. 분석되었다. 본 연구에서 제작된 소자들은 금속-절연층-금속의 다층구조로 100 micron 미만의 소자두께를 가지며 $300{\sim}1200$ Torr의 Neon, Xenon 및 여러 기체 mixture에서 안정되게 구동되었고 구동전압은 $100{\sim}150V$ 범위로 관찰되었다. 이 밖에도 대면적 어레이내 소자간 병렬구동을 위한 다양한 구조의 소자들이 제작되었으며, 이들의 방전 및 발광특성, 그리고 전기적 특성이 분석되었다.

In this paper, to developing thermally and mechanically upgraded ones, we dismounted pole transformers used in the fields for over 13 years and conducted aged oil analysis. Also, when the cellulose and aramid papers in test cell were aging with oil at $130^{\circ}C$ for 3000 hours, with the testing period cellulose paper deteriorated more rapidly than the others. For example dielectric strength and dissipation factor of papers deteriorated with aging time. For evaluation of thermal aging characteristics, a mineral oil-immersed transformer was constructed with hybrid insulation system comprised of aramid paper and cellulose insulation. A Hybrid system has economic advantages. Cellulose materials are confined to cooler regions of the transformer winding. And aramid papers are served to insulate contact parts of hot conductors.

KEPCO is planning to operate 765kV Sin-Tao-Back and Sin-Ga-Pyong substations from 2004. A preventive diagnostic system to obtain the reliability of transformer and GIS is being adopted in 765kV substations. KEPRI has developed a preventive diagnostic system for 765kV substation since 1997. The preventive diagnostic system developed in that project was installed to the 345kV Eui-Ryung substation in June, 2000, and it is under circumstance durability test and operation capacity tests. In this paper, we analyze data of the preventive diagnostic system in 345kV Eui-Ryung substation.

The degree of contamination on outdoor insulator is one of the most important factors for the determination of insulation level. And the salt, NaCl, is known as the most dangerous contaminants in the most region of the world. As shown through the preceding study, we could find the close relationship between the generation and deposition of salt contaminants and the meteorological conditions. To analyze the relationship, we monthly measured the ESDD for some sites with brush wiping method, and daily measured the density for one site with the automatic measuring apparatus. And, with the measured data and the meteorological data from KMA(Korea Meteorological Administration), we analyzed the relationship between the two factors with regression method. Through the results of this investigation, we could quantify the comparative contribution of the climatic factors for the pollution level of outdoor insulator, and the results could be used as a useful reference for the maintenance of overhead lines and substations.

In general, ZnO lighting arrester are known to exhibit an increases in resistive current with time, the rate of increase being exacerbated with increasing applied voltage. In addition, since the resistive leakage current caused by deterioration of ZnO lighting arrester mainly caused an increase of the third harmonic component, thereby it is possible the arrester degradation diagnosis by measuring the third harmonic component in the total leakage current. So, in this paper, we presents a leakage current measuring and analysis system of 18[kV] ZnO lighting arrester.

Recently, domestic electrical parts and materials without safety and reliability are avoided by consumers and introducing the product liability (PL) law. Therefore, the dependance on import product of electrical machines will be increased in the future. In this paper, high-voltage induction motor ensures reliance that can maintain the performance of machines for a long time. Furthermore, the test of reliability evaluation that predicts a remaining life and breakdown test of the stator winding are performed. Also, this paper introduces various reliability assessment tests for getting reliability of the stator winding insulation in high-voltage motor.

본 논문에서는 non-radiative dielectric (NRD) guide를 이용한 듀플렉서를 설계하였다. 설계된 듀플렉스는 두 개의 gap-coupled 필터와 T-junction으로 구성되어 있다. Gap-coupled 필터의 설계에는 차단 주파수 영역 등가회로를 이용하였으며 T-junction은 30dB 이상의 반사손실을 갖도록 최적화하여 두 가지의 형태로 설계하였다 위의 설계과정을 통하여 1% 대역폭, 0.1dB ripple, 37.7 및 38.3 GHz의 중심주 파수를 갖는 듀플렉서를 설계하였다. 두 가지 형태의 결합부를 갖는 듀플렉서에 대해 시뮬레이션하여 응답특성을 비교한 결과 듀플렉서의 응답특성이 원하는 결과에 근접하게 나옴을 확인하였다.

In this paper, we were designed the ferroelectric phase shifter using 3-dB, $90^{\circ}$ branch-line hybrid coupler with two ports terminated in symmetric phase-controllable reflective networks. The design of phase shifter is based on reflection theory of terminating circuits. In order to find the optimum conditions of reflect phase, the effect of a change of capacitance and transmission line connected with two coupled ports of a coupler have been investigated. To obtain more accurate design parameters, finite element method is applied. We were showed large phase variation with small capacitance variation in the parallel connection of capacitor and transmission line by using EM-simulation and circuit-simulation.

본 논문은 편광 유지 광섬유 루프 미러를 이용한 색분산 보상 필터의 제안과 이의 응용에 관한 것이다. 제안된 필터는 구성이 간단하고, 편광 의존성이 낮으며 하나의 장비로 여러 채널의 신호를 동시에 분산 보상할 수 있는 장점이 있다. 실험에 사용된 커플러의 파워-커플링 계수를 조절하면 그룹 딜레이 기울기를 조절할 수 있다. 그리고 n개의 편광 유지 광섬유 루프 미러클 연결하면 필터의 손실이 커지지만 커플링 계수의 조절을 통해 필터 특성을 변화시킬 수 있다. 이와 같은 특성을 이용하면 제안된 필터를 동적 분산 보상기로 이용할 수 있다. 논문에서는 파워-커플링 계수의 변화에 따른 필터의 그룹 딜레이 기울기의 변화를 계산한 그래프와 실험 결과 데이터를 비교 제시하였다.

The optical current transformer using Faraday effect is the sensor to measure current that flows in any conductor. This sensor doesn't undergo the magnetic saturation and effect of adjacent conductors. But this senor using bulk-glass sensing clement has crucial drawback. It is impossible that the sensor is mounted to conductor without breaking the closed-loop of light or conductor. So we developed the clamp-type optical current transformer and made an experiment.

기존의 3차원 형상 측정법은 대부분 접촉식이기때문에 피측정물이 손상이 입거나 Probe의 보정이 필요하거나 Probe가 측정면에 직접 닿지 않는 경우는 측정이 불가능하였다. 또한 많은 점을 측정할 경우측정시간이 많이 걸린다. 물체의 크기가 크거나 측정하고자하는 물체가 무를 경우에는 적합하지 못하다. 이러한 단점은 보완하기 위하여 비접촉식인 측정법 이용한 관측이 대두되게 되었다. 비접촉식에 의한 관측은 물체의 표면을 손상시키지 않으면서 정밀하고 고품질이 요구되는 제품 검사 및 자동화 기술의 발달로 인하여 생산 산업 분야에 이용되고 있다 이에 비접촉식 방식에서도 광학간섭의 하나인 마이켈슨 간섭계를 이용하여 간섭무늬 패턴으로 물체 이미지를 분석하고 CCD카메라에서 영상을 얻어 3차원 물체를 해석하였다.

In this paper, some parameters are studied for the performance improvement of a bulk optical current sensor. The performance of optical current sensor is influenced by current measuring range, Verdet constant change due to temperature change, temperature variation of wave plate, signal to noise ratio of optical transmitter/receiver, optical bias mismatch. Two types of optical current sensors are implemented and tested in the current range from 10 ampere to 200 ampere.

In this paper, we present a study of the structure and electro-optic behavior of hybrid liquid-crystal-silica sphere composite photonic crystals, formed by filling the (26% by volume) void space of fee (face centered cubic) silica opals infiltrated with a nematic liquid crystal. Three dimensional photonic crystals of visible range were fabricated via a self assembly method of silica spheres of submicron diameter. The expected fee structure was confirmed by scanning electron microscopy (SEM) of the dehydrated crystal with glass removed. The photonic crystal exhibited significant electric-field-induced shift of the optical Bragg reflection peak when the liquid crystal has the long molecular axis oriented parallel to the sphere surfaces.

A tunable fiber laser and the Quadrature Sampling technique are used to construct highly sensitive fiber-optic distributive Bragg grating strain sensor system. By using a wavelength-modulated fiber laser, the variations of strain-dependent Bragg wavelengths are transformed into the variations of time-domain reflection profiles. The locations of profile peaks that correspond to the applied strains are demodulated using a precise wavelength encoder that uses a fiber-optic Mach-Zehnder interferometer and Quadrature Sampling technique. With the extremely high sensitive optical encoder, we could obtain not only high sensitivity, but also very linear responses that was impossible with the conventional techniques. This paper is attempted to report the theoretical and experimental results.

Numerical simulation for effect of chirp on PMD and PDL was accomplished. we assumed two uniform fiber concatenation with both polarization mode dispersion and polarization-dependent loss. We showed that polarization mode dispersion is increased with chirp parameter and polarization-dependent loss is decreased with chirp. And we accomplished mathematical analysis.

선복굴절과 원복굴절을 갖는 광섬유의 원편광 복굴절 해석을 비틀림을 준 단일광섬유 및 이종광 섬유에 대하여 Faraday 회전에 대한 변조깊이로 나타내었으며, 이종광섬유를 사용할 경우, 출력 편광을 조정 할 수 있으며, 또한 이종광섬유를 사용함으로서 비틀림율이 낮을 경우에도 적절한 변조 깊이를 얻을 수 있었다. 이때, 비틀림 율은 12-20turns/m 정도였다.

본 논문에서는 마이크로스트립 방향성 결합기의 지향성을 향상시키기 위한 최적설계를 수행하였다. 제안된 설계는 기존의 지향성을 향상시키기 위한 다른 시도들과는 달리 하우징 구조를 설계함으로써 비교적 제작하기가 수월한 장점이 있다. 최적화를 위해서 결정론적 알고리즘과 결합된 (1+1)진화 알고리즘을 적용하였으며, 최적화결과 보다 향상된 방향성 결합기의 특성을 얻을 수 있었다. Ansoft-HFSS를 이용하여 해석결과의 타당성을 검증하였다.

본 논문에서는 밀리미터파 대역에서 저손실 특성이 우수한 전송선로인 non-radiative dielectric (NRD) guide와 microstrip의 transition에 관해 연구하였다. 본 연구에서 이용된 transition은 aperture coupling을 이용한 것으로 NRD와 microstrip 사이의 aperture를 통하여 magnetic field가 coupling되는 원리이다. Aperture의 구조를 각각 rectangular와 ridge 형태로 설계하였다. 비교를 위해서 설계된 microstrip to microstrip transition의 경우 aperture의 구조를 ridge 형태로 했을 때 rectangular 일 때 보다 삽입손실 특성이 개선되었고 더 넓은 bandwidth를 가지는 것을 알 수 있었다 NRD to microstrip transition의 경우는 bandwidth 면에서 ridge 구조와 rectangular 구조 모두 비슷한 특성을 보였다.

원자력 발전소 방사성 잡음 규제기준을 설정하기 위하여 발전소 내의 전자파 잡음 환경을 측정하였다. 대상 발전소는 1000 MW급 울진 원자력발전소 3호기로 발전소 출력 0 %에서부터 100 %까지 10일간 주 제어실 및 전기설비실 주변을 대상으로 US NRC Reg. Guide 1.180 및 Mil-Std-462D를 측정기준으로 하여 전기장 10 kHz ${\sim}$ 7 GHz. 자기장 30 Hz ${\sim}$ 100 kHz의 방사성 잡음을 측정하였다. 측정결과를 최소자승법을 이용한 회귀분석으로 잡음 한계값을 유도하여 미국 EPRI 및 NRC 측정결과와 비교한 결과 자기장의 경우 낮은 한계값을 보였고 전기장의 경우는 20 dB 이상 높게 결정되었다.

An efficient automatic mesh generator suitable for the harsh model, which contains abrupt regions and thin layers, is implemented. It adopts two kinds of node placement scheme. In the beginning, the initial nodes on the boundary are generated automatically by an efficient boundary node generation scheme. And then the inner nodes are placed using nodal spacing value technique repeatedly from the initial mesh to final mesh. The effectiveness of the proposed technique is verified by a thin film micro-strip line modeling, where the final mesh contains no sliver elements.

This paper reviews the calculation of induced voltage to a communication line from Power Transmission Line. Power lines, both overhead and underground, often run parallel to weak current lines, such as telecommunication, signal or data transmission systems or protection circuits. The coexistence of both systems in parallel over long lengths is accompanied by the possible induction of significant longitudinal voltage in the weak current line. In order to evaluate a precise induced voltage, this paper indicated problem about coefficient and numerical formula and present some induced voltage production technology standard application.

Requirements for high-efficiency equipment for energy saving are rapidly increasing recently keeping pace with development of digital and semiconductor technology. Accordingly, there are many changes and development in ballast. Ballast currently in use are Magnetic ballast (Coiled Type) and Electronic ballast. Electronic ballast produces incredible energy saving effect, but falls short of confidence instead. In addition, use at higher frequency through switching device creates Electromagnetic Interference (EMI) and high frequency. EMI creates low quality of equipment, damage in facilities and low productivity by leading miss operation of equipment, and interferes with surrounding machines. In this analysis I am going to examine characteristics of EMI on the Electronic ballast of FLR32SS one type pursuant to annex 3 of Electric Goods Technology Standard, and counter technology.

The hand-piece fiber optics is applied to medical appliances such as glaucoma theraphy to focus semiconductor laser on the affected parts efficiently. In this paper, we evaluate optical properties such as beam power and radius of a hand-piece probe by experiments and we also simulate the hand-piece optics by ray tracing method in order to study major parameters to optimize focalization ability. As results, we show experimental and simulation results of the hand-piece optics and also summarize several requirements that have to be considered in optimizing the hand-piece optics.

This paper reports on the single mode fiber coupling efficiency. There is difference between simulation by CODE-V and theoretical result, we observed CEO which is taken by experiment in lab and found out that CEO taken by CODE-V was closer to real experiment result then theoretical result.

This paper presents the design and performance of low pull-in voltage MEMS switches for commercial cellular/PCS applications. The switches have all-metal (3 ${\mu}m$ thick Au) movable plates over CPW(Coplanar Waveguide) transmission line. The stress gradient in a movable plate is considered in mechanical design to obtain an accurate pull-in voltage. Series metal-to-metal contact switches are fabricated and evaluated. Those switches exhibit the low loss(<0.2 dB @1.9 GHz) with good isolation(55 dB @1.9 GHz).

In this paper, we have proposed low temperature co-fired ceramic (LTCC) based packaging for RF MEMS devices. The packaging structure is designed and evaluated with 3D full field simulation. 50 ${\Omega}$ matched coplanar waveguide(CPW) transmission line is employed as the test vehicle to evaluate the performances of the proposed package structure. The line is encapsulated with the LTCC packaging lid and connected to the via feed line. To reduce the insertion loss due to the packaging lid, the cavity with via post is formed in the packaging lid. The performances of the package structure is simulated with the different cavity depth and via-to-via length. Simulation results show that the proposed package structure has reflection loss better than 20 dB and insertion loss lower than 0.1 dB from DC to 30 GHz with the cavity depth and via-to-via length of 300 ${\mu}m$ and 350 ${\mu}m$, respectively. To realize the designed package structure, the cavity patterning is tested using the sandblast of LTCC.

micro CPL 제작을 위한 LICA 및 MEMS 공정을 개발하였으며 양산화를 위한 새로운 방법으로 ${\mu}$MIM(micro Metal Injection Molding) 기술을 제안하였다. 먼저 LIGA 기술을 이용하여 Cu 도금 구조물로 이루어진 micro CPL 구조물을 제작하였다. 각각 상판과 하판 구조물로 나누어 제작하였으며 상, 하판 Cu 구조물을 brazing 방법을 이용하여 접합하였다. 또한 micro CPL 내부에서 일어나는 냉매의 흐름 및 상변화(liquid ${\leftrightarrow}$ vapor) 거동을 관찰할 수 있는 새로운 개념의 Si/glass 투명 micro CPL을 제작하였다. 상기 공정을 이용하여 냉각 능력이 10w/$cm^2$ 이상인 micro CPL을 제작하였다. 상기 연구 결과를 바탕으로 양산화를 위한 새로운 정밀복제기술인 ${\mu}$MIM(Micro Metal Injection Molding) 공정을 개발하였다. LISA 공정으로 제작된 정밀 금형을 core금형으로 사용하였고 $1{\mu}m$ 이하의 W-Cu(10%) powder와 binder가 혼합된 흔합분말을 이용하여 micro channel 구조물(선폭 $100{\mu}m$)의 성형 복제에 성공함으로서 양산화를 향한 기반기술을 확립하였다.

새로운 방식의 일체형 flexible sensor module을 제작하였다. MEMS공정을 이용하여 제작된이 센서 모듈은 배선기판은 물론 strain sensor 역시 임의의 곡면에 실장을 위해 자유로운 굽힘이 가능하도록 제작되었다. 실리콘웨이퍼에 구현된 piezoresistor 스트레인 센서는 release-etch 방법을 통해 웨이퍼로부터 분리되어, 폴리이미드를 기판으로 하는 Flexible Sensor Array Module로 완성되었다. 소자와 기판을 따로 제작한 후 조립하는 기존의 방식에 비해, 웨이퍼 위에서 flexible 기판을 형성하여 수율이 높고 사진공정의 정밀도를 그대로 보전한 기판과 센서 어레이의 패키징이 가능하였으며, 칩을 기판에 실장하기 위한 정밀한 조립공정도 불필요하였다. 폴리이미드 기판은 전기도금을 통해 회로를 구성하여 1단계 패키징 (die to chip carrier)과 2단계 패키징 (chip to substrate)을 웨이퍼 레벨에서 완성하였다. 마지막으로 불산 용액을 통해 희생층을 제거함으로서 웨이퍼로 부터 센서어레이 모듈을 분리 하였다.

The admittance of one-port electrostatic actuator are modeled using the steady-state sinusoidal response. Also the admittance of the differential type actuator is derived taking the practical conditions into consideration, although it has no admittance in ideal case. It is a function of biasing error, driving error, and capacitive mismatch including parasitic capacitors. The validity of the admittance model is proved by comparing between the modeled and measured admittances. The distortion in the frequency response curve measured by a capacitive sensor is analyzed and it is concluded that the admittance is the main cause of this distortion.

Silicon bulk micromachined micromirrors are designed and fabricated for out-of-plane right angle reflection. The micromirror is comprised of a minor plate, springs, magnetic bars and electrodes. Single crystalline silicon is used for a flatness improvement of a mirror plate. Out-of-plane right angle reflection requires a 45 degree operation of the micromirror. The micromirrors are operated by applying a magnetic field, which is generated by a coil located below a substrate. For an individual mirror operation, each mirror is clamped using an electrostatic force against the electromagnetic force. Angular deflections are measured and compared with theoretical data. The micro mirror operates up to 45 degree when magnetic field is 4 kA/m which is generated by a 115 mA coil current Simple addressing is tested, and it is shown that a clamping voltage is less than 5V.

마이크로 바이오칩용 미세 무게 감지 소자를 개발하기 위해 통상적인 MEMS 공정에 PZT sol solution을 함침하여 binder로서 적용하는 복합적인 스크린 인쇄 방법을 적용해 $800-850^{\circ}C}$의 비교적 저온에서 높은 소결밀도와 우수한 전기적인 특성을 가지는 PZT-0.12PCW 후막 구동형 캔틸레버 소자를 Pt/$TiO_2$/YSZ/$SiO_2$/Si 기판에 제조하였다. 제조된 PZT-0.12PCW 후막 구동형 캔틸레버 소자의 공진 주파수와 변위를 레이저 미소 변위 측정 시스템을 이용하여 공기 중 및 액체 중에서 측정함으로써 캔틸레버 크기에 따른 공진 특성 변화, 액체 내에서의 댐핑 효과 등을 분석할 수 있었다. 또한 Au를 증착하거나biotin-streptoavidin 반응을 통해 단백질을 고정화시켜 무게변화를 야기시킨 후 소자의 감도를 평가함으로써 PZT-0.12PCW 후막 구동형 캔틸레버를 우수한 성능의 바이오칩용 미세 무게 감지 소자로 응용할 수 있음을 알 수 있었다.

This paper presents the PDMS surface characteristic change after the plasma process and the electroosmotic flow control technique for the two-dimensional focusing in the micro channels made of PDMS and glass. The channels are fabricated by plastic molding and micromachining technique. To observe the surface characteristic change as time elapses, we measure the contact angle of water on the surface and the velocity of the electroosmotic flow in a channel. The electric field adequate for focusing of a core flow in a confluence channel is obtained by the experiment. The computer simulation is performed to obtain the width and the depth of the core flow for several junction angles of the confluence channel.

This paper reports a novel high-speed fluid injection system employing a simple magnetic micoractuator. This magnetic microacutator consists of current carrying copper beams and permanent magnet under the beams. There were many efforts to magnetic microactuator realization using conducting coils [1-2]. Even though many of magnetic microactuators were successfully fabricated and tested, it is true that most them suffer complex fabrication processes and thus higher production costs than electrostatic counterparts. In this research, efforts were concentrated on the microactuator realization that has simple structure, low production cost, and mass production possibility.

고분자 주쇄(Main chain)의 소수성을 가지는 플루오르 그룹을 배제시킨 습도 민감성 폴리이미드를 합성 및 이미드화 하였고, 이를 이용한 초고참도 습도 센서를 제작 및 측정하였다. 사용된 폴리이미드는 다이아민계로 Oxydianyline(ODA)와 다이안하이드라이드계로 Pyromellitic dianhydried(PMDA)를 유기용매 Dimethyla cetamide(DMAc) 하에서 폴리이미드 전구체 (Polyamic acid)를 합성하였으며, 진공 및 승온 조건에서 유기용매를 제거하여 이미드화(Imidization) 반응을 진행시켜 제조하였다. 본 습도 센서는 정전용량형 고감도 습도 센서로 디자인되었으며 실리콘 웨이퍼상에서 일반적인 반도체 공정을 이용하여 구현하였다. 본 습도 센서는 센서 크기와 유효면적, 감습층의 두께를 주요 변수로 설정하였으며 이에 따른 습도 민감성 효과를 평가 및 분석하였다. 측정 결과 유효면적 70%, 감습층 두께 $1.1{\mu}m$ 로 제작된 습도 센서는 상대숨도$20%{\sim}90%$ 영역에서 캐패시턴스와 선형적 상관관계를 보여주고 있으며, 습도 민감도는 3.9 pF/%RH 클 얻을 수 있었다.

신장병의 조기진단을 위해서 체내의 요소 농도의 정확한 측정은 매우 중요하며, 이러한 이유에서 많은 연구자들은 보다 빠르고 정확한 체내의 요소농도 측정을 위한 바이오센서를 개발 중이다. 본 논문은 반도체 공정을 이용하여 산화막(4.000${\AA}$)이 성장된 p-형 실리콘 웨이퍼를 사용하였다. RF sputter를 사용하여 티타늄과 백금을 증착한 백금 박막전극을 제작하였다. 그 위에 전도성 고분자인 Polypyrrole(PPy)과 전도도를 증가시키기 위하여 구리를 도펀트로 사용 scan rate 40mV/S $0.8{\sim}-0.8V$ 전위영역에서 산화적 전기 중합법 (anodical electropolymerization)을 이용하여 전극을 형성하였다. 요소를 2개의 암모늄 이온과 1개의 탄산 이온으로의 가수분해반응을 촉매하는 효소로써 유레이즈(urease)를 전기적 흡착방법을 이용하여 고정화하고 이에 요소농도의 변화에 대하여 시간대 전류법 (chronoamperometry:CA)을 사용하여 감도를 측정하였다. 최적화된 조건하에서 요소농도에 비례하여 Cu-doped PPy electrode로부터 얻어진 확산한계전류는 $4.5{\mu}A$/decade의 기울기를 나타내었다. 전극의 표면은 SEM(Scanning Electron Microscopy)과 EDX(Energy Dispersive X-Ray Spectrometer)를 이용하여 분석 하였다.

바이오 마이크로 시스템 및 바이오 MEMS 분야, 특히 실리콘을 기질로 하는 바이오 센서 제작에서 반도체 공정 기술은 센서의 대량 생산과 초소형화를 위해서 반드시 필요한 기술이다. 그러나, 감지전극의 마이크로화에 따른 센서의 감도 및 안정성 저하 문제는 해결해야 할 과제이다. 최근, 다공질 실리콘이 갖는 대면적이 실리콘 기질과 생체 고분자 (예: 단백질, 핵산 등) 간의 결합력을 향상시킬 수 있음이 알려지면서, 바이오 센서 분야에서, 새로운 형태의 드랜스듀서 재료로서의 다공질 실리콘에 대한 논의가 활발히 전개되고 있으며 또한, ISFET (Ion-Selective Field-Effect Transistors) 와는 달리 다공질 실리콘 층은 저항이 크기 때문에 센서 제작 과정에서의 부가적인 절연막을 필요로 하지 않는다. 본 연구에서는, 백금을 증착한 다공질 실리콘 표면에 전도성 고분자로서 Polypyrrole (PPy) 필름과 생체 고분자 물질로서 Urease를 각각 전기화학적으로 흡착하였다. 다공질 실리콘 층의 형성을 위해 테플론 소재의 전기화학 전지에 불산 (49%), 에탄올 (95%), $H_2O$ 혼합 용액을 넣고 실리콘 웨이퍼에 일정시간 수 mA의 산화 전류를 흘려주었으며, 약 $200{\AA}$의 티타늄 박막과 $200{\AA}$의 백금 박막을 RF 스퍼터링하여 작업 전극을 제작하였고, 백금 박막 및 Ag를 기화 증착하여 제작한 Ag/AgCl 박막을 각각 상대 전극과 기준전극으로 하였다. 박막 전극의 표면 분석을 위해 SEM (Scanning Electron Microscopy), EDX (Energy Dispersive X-ray spectroscopy) 등을 이용하였다. 제작된 요소 센서로부터 요소 농도 범위 0.01 mmol/L ${\sim}$ 100 mmol/L에서 약 0.2 mA/decade의 감도를 얻었다.

MEMS 공정을 이용하여 $SiN_x$를 지지층으로 한 $SiO_2$/Ta/PZT/Pt 의 박막 구조를 가지는 마이크로 켄틸레버를 제작하였다. 켄틸레버의 전기기계적 특성을 LDV (레이저 미소 변위 측정기)를 이용하여 측정하였으며, 이를 통해 전기기계적 거동을 분석하였다. 또한 무게 감지소자로서의 응용을 위해 Au의 증착을 통한 감도를 측정하였으며, streptavidin의 무게를 감지하기 위해 immobilization 공정을 거쳐 thiol 그룹 및 biotin을 표면에 고정화 시킨후 biotin-streptavidin 결합에 의한 전기기계적 신호 분석을 통해 생체 물질의 무게 감지 소자로의 응용을 평가하였다.

Process conditions of a novel negative thick photoresist, JSR THB-$430N^{(R)}$, are established in this paper. Although SU-8 obtains uniform and high-aspect-ratio structures, it is hard to remove the SU-8 mold after electroplating. The JSR THB-$430N^{(R)}$ can be more easily removed than the SU-8 and has a low internal stress. Introducing two step strip processes using acetone and the jSR THB-$S1^{(R)}$, the JSR THB-$430N^{(R)}$ electroplating mold was removed completely and a JSR THB-$430N^{(R)}$ film stress is compressive less than 2 MPa. In this paper, we obatined $200{\mu}m$ thick PR structure and $100{\mu}m$ thick electroplated nickel structure using the JSR THB-$430N^{(R)}$ photoresist.

일반적으로, 전도성 고분자는 금속에 준하는 전기 전도도와 다공성을 이용한 전해질 이온 및 생채 고분자의 물리, 화학적 도우핑 능력을 장점으로 한다. 따라서, 이 분야의 최근 연구동향도 이온 도우핑에 의한 전도성 고분자의 전기 전도도 향상에 초점이 맞추어져 있으며, 이미 다수의 연구진에 의행 여러 가지 방법이 제시되었다. 본 논문은 전기 화학적 cementation 공정을 이용하여 금속 이온을 전도성 고분자에 도우핑하고 특성을 고찰하였다. 전도성 고분자로써 polypyrrole (PPy)을 사용하고, micropaticles (구리와 니켈 이온)를 도펀트 (dopant)로 하여 -1.5 V ${\sim}$ 2V의 범위에서 순환 전압 전류법 (Cyclic voltammetry)을 이용해 organic-inorganic complex를 제작하였고, 각각의 전극을 비교, 분석 하였다. 구리 이온을 도우핑한 PPy 필름은 전기 전도도가 매우 우수하나 대기 중 공기 및 수분에 의해 쉽게 산화되므로 life-time이 짧다. 이를 보완하기 위하여 상대적으로 안정한 니켈 이온을 도우핑한 PPy 필름의 전기 화학적 특성을 고찰하였다. 전극의 표면은 SEM (Scanning Electron Microscopy), EDX (Energy Dispersive X-ray spectroscopy)를 이용하여 분석하였다.

Liquid crystal displays(LCDs)의 스위칭 소자로써 thin film transistors(TFTs)를 적용하기 위해서 저온 공정이 가능하도록 molybdenum 금속을 게이트에 사용하여 저온 다결정 TFTs 소자를 제작하였다. 또한, 채널 길이 방향으로 결정을 성장시켜 결정립이 큰 다결정 실리콘을 얻을 수 있는 sequential lateral solidification(SLS) 결정화 방법을 사용하였다. SLS-TFT 소자를 $2{\mu}m$에서 $20{\mu}m$까지의 다양한 채널 길이와 폭으로 제작한 후 각 소자들의 I-V 특성 곡선과 소자의 물성 분석을 위해 필요한 변수들을 구하여 이들의 전기적인 특성을 비교, 분석하였다. 제작된 소자들로부터 측정된 이동도는 $100{\sim}400Cm^2$/Vs, on/off 전류비는 약 $10^7$, off-state 전류는 약 $100{\times}10^{-12}A$로 대체적으로 우수한 특성을 보였다.

미세 형광을 측정하기 위해 초소형 프리즘, 렌즈 및 거울로 구성된 초소형 스캐닝시스템을 설계하고 그 특성을 시뮬레이션 하였다.

SiC direct bonding technology is very attractive for both SiCOI(SiC-on-insulator) electric devices and SiC-MEMS fileds because of its application possibility in harsh environements. This paper presents on pre-bonding according to HF pre-treatment conditions in SiC wafer direct bonding using PECVD oxide. The PECVD oxide was characterized by XPS and AFM, respectively. The characteristics of bonded sample were measured under different bonding conditions of HF concentration and applied pressure, respectively. The bonding strength was evaluated by tensile strength method. Components existed in the interlayer were analyzed by using FT-IR. The bond strength depends on the HF pre-treatment condition before pre-bonding (Min : 5.3 kgf/$cm^2{\sim}$ Max : 15.5 kgf/$cm^2$).

We have fabricated a novel vertical trench-Hall device sensitive to the magnetic field parallel to the sensor chip surface. The vertical trench-Hall device is built on SOI wafer which is produced by silicon direct bonding technology using bulk micromachining, where buried $SiO_2$ layer and surround trench define active device volume. Sensitivity up to 350 V/AT is measured.

본 논문에서는 실리콘 기판상의 전송선로 특성을 개선하기 위하여 표면 마이크로머시닝 기술을 이용하여 $10{\mu}m$ 두께의 다공질 실리콘 산화막으로 제조된 기판 위에 에어브리지를 가진 CPW 전송선로와 phase shifter를 제작하였다. 간격이 $30{\mu}m$, 신호선이 $80{\mu}m$인 CPW 에어브리지 전송선의 삽입손실은 4 GHz에서 -0.25 dB이며, 반사손실은 -28.9 dB를 나타내었다. CPW phase shifter의 크기는 S-W-$S_g$ = 100-30-400 ${\mu}m$로 설계되었다. "ㄷ" 모양을 가진 에어브리지의 폭은 $100{\mu}m$. 길이는 400-460-400 ${\mu}m$이다. 낮은 손실을 얻기 위한 Step된 에어브리지를 가진 phase shifter 구조가 step이 없는 에어브리지를 가진 구조보다 삽입손실이 보다 더 향상되었다. 제작된 CPW phase shifter의 위상특성은 28 GHz의 넓은 주파수 범위에서 $180^{\circ}E 의 천이를 타나내었다. 이상과 같은 결과로부터 두꺼운 다공질 실리콘은 고 저항 실리콘 집적회로 공정에서 고성능 저가의 마이크로파 및 밀리미터파 회로 응용에 충분히 활용 될 수 있으리라 기대된다.