• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1995년도 하계학술대회 논문집 C
• /
• pp.1168-1170
• /
• 1995

The purpose of this thesis is to fabricate the hexamethyldisiloxane thin film by plasma polymerization method, and to investigate the electric conduction characteristics of plasma polymerized thin film. Current density was measured in being changed annealing temperature(room temperature${\sim}125[^{\circ}C]$) and electric field intensity($10^5{\sim}1.2{\times}10^6$[V/cm]). The current density of thin films fabricated at discharge power of $30{\sim}90$[W] showed $1.3{\times}10^{-11}{\sim}3.1{\times}10^{-12}[A/cm^2]$ after 10 minutes of permission of electric field. The current density increased gradually with increasing of annealing temperature and electric field intensity. The electric conduction type of thin films fabricated in discharge power of 90[W] agreed with Schottky type.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제50권11호
• /
• pp.555-561
• /
• 2001

In this paper, the low power (1.5 W) solenoid-type magnetic thin-film transformers utilizing a $Ni_{81}Fe_{19)$ core material were designed and fabricated for 5 MHz-drive DC-DC converter application. The $20\mum$ thick copper films were used as the coils. The transformers fabricated in this work have the sizes of $3.08 mm\times25.5 mm\; and\; 6.15 mm\times12.75 mm.$ The optimum design of solenoid-type magnetic thin film transformers was performed utilizing the conventional equations, a Maxwell computer simulator (Ansoft HFSS V7.0 for PC), and parameters obtained from the magnetic properties of NiFe magnetic core materials. frequency characteristics of inductance, dc resistance (R), coupling factor (k) and gain of developed transformers were measured using HP4194A impedance and gain-phase analyzer. The fabricated transformers with the size of $6.15 mm\time12.75 mm$ exhibit the inductance of $0.83 \muH$, the dc resistance of $2.3\Omega$$\Omega$, the k of 0.91 and the gain of -1 dB at 5 MHz, which show the comparable results to those reported in the recent literatures. The measured high-frequency characteristics for the fabricated transformers agreed well with those obtained by theoretical calculations .

• 한국재료학회지
• /
• 제27권5호
• /
• pp.289-293
• /
• 2017

$Y_2Ti_2O_7$ nanoparticles (0.3 mol%) have been successfully synthesized by the co-precipitation process. The samples, adjusted to pH7 with ammonia solution as catalyst and calcined at $700{\sim}900^{\circ}C$, exhibit very fine particles with close to spherical shape and average size of 10-30 nm. It was possible to control the size of the synthesized $Y_2Ti_2O_7$ particles by manipulating the conditions. The $Y_2Ti_2O_7$ nanoparticles were coated on a glass substrate by a dipping coating process with inorganic binder. The $Y_2Ti_2O_7$ solution coated on the glass substrate had excellent adhesion of 5B; pencil hardness test results indicated an excellent hardness of 6H. The thickness of the thick film was about $30{\mu}m$. Decomposition of MB on the $Y_2Ti_2O_7$ thin film shows that the photocatalytic properties were excellent.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2003년도 추계학술발표회초록집
• /
• pp.119-119
• /
• 2003

Plasma polymerized organic thin films were deposited on Si(100) glass and Copper substrates at 25 ∼ 100 $^{\circ}C$ using cyclohexane and ethylcyclohexane precursors by PECVD method. In order to compare physical and electrochemical properties of the as-grown thin films, the effects of the RF plasma power in the range of 20∼50 W and deposition temperature on both corrosion protection efficiency and physical properties were studied. We found that the corrosion protection efficiency (P$\_$k/), which is one of the important factors for corrosion protection in the interlayer dielectrics of microelectronic devices application, was increased with increasing RF power. The highest P$\_$k/ value of plasma polymerized ethylcyclohexane film (92.1% at 50 W) was higher than that of the plasma polymerized cyclohexane film (85.26% at 50 W), indicating inhibition of oxygen reduction. Impedance analyzer was utilized for the determination of I-V curve for leakage current density and C-V for dielectric constants. To obtain C-V curve, we used a MIM structure of metal(Al)-insulator(plasma polymerized thin film)-metal(Pt) structure. Al as the electrode was evaporated on the ethylcyclohexane films that grew on Pt coated silicon substrates, and the dielectric constants of the as-grown films were then calculated from C-V data measured at 1㎒. From the electrical property measurements such as I-V ana C-V characteristics, the minimum dielectric constant and the best leakage current of ethylcyclohexane thin films were obtained to be about 3.11 and 5 ${\times}$ 10$\^$-12/ A/$\textrm{cm}^2$ and cyclohexane thin films were obtained to be about 2.3 and 8 ${\times}$ 10$\^$-12/ A/$\textrm{cm}^2$.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 1992년도 추계학술대회 논문집
• /
• pp.73-76
• /
• 1992

The amorphous phase of bulk and thin film in the As-Se-S-Ge system was observed by X-ray diffraction. Thermal analysis using DSC, DTA and TGA method has been used for the determination of the glass transition temperature, Tg. The glass transition temperature, Tg for the composition were $238^{\circ}C$ in $As_{40}Se_{15}S_{35}Ge_{10}$ and $231^{\circ}C$ in $AS_{40}Se_{25}S_{25}Ge_{10}$ and $As_{40}Se_{50}Ge_{10}$. The phase seperation of continuous phase and dispersive phase was observed by the optical texture of the polarizing microscope. Also, the glass transition temperature of the thin film was near $200^{\circ}C$. As the results of SEM-EDS analysis, the phase transition of the films by thermal treatment and light illumination was the amorphous to amorphous.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1997년도 하계학술대회 논문집 C
• /
• pp.1546-1548
• /
• 1997

We investigated microhardness, friction, wear and wettability of polyimide for finding out the influence of ion implantation on surface properties. For increasing doses microhardness increased. A reduction of the friction coefficient was most cases correlated with a reduction of wear. The contact angles of water for $B^+$, $N^+$ implanted polyimide decreased from $76^{\circ}$ to zero, as the fluences increased energy of 50, 200 keV.

• 한국식품저장유통학회지
• /
• 제23권5호
• /
• pp.623-630
• /
• 2016

본 연구는 신선편이 양파의 포장방법 및 저장온도가 신선편이 양파의 선도유지 및 품질에 미치는 영향을 알아보기 위해 저온 저장 중인 양파를 뿌리 및 줄기 부분을 절단하고 껍질을 제거하는 등 최소로 가공한 양파를 준비하였다. 최소가공 한 신선편이 양파는 polyethylene(PE, $50{\mu}m$) 필름에 밀봉 포장하거나 polyethylene/polypropylene(PE/PP, $100{\mu}m$) 필름에 진공 포장하고, $4^{\circ}C$ 및 $10^{\circ}C$에 저장하면서 21일 동안 미생물 분석, 색도, 산도, pH, 포장 내 기체변화, 관능적 품질을 조사하였다. 미생물 분석 결과 총 세균 및 대장균군의 밀도는 포장방법보다는 신선편이 양파의 저장온도에 큰 영향을 받았으며, $10^{\circ}C$보다는 $4^{\circ}C$에 저장했을 때 세균의 밀도가 낮았다. 곰팡이는 PE 필름에 밀봉 포장하여 $10^{\circ}C$에 저장했을 때 저장 13일부터 다른 처리구에 비해 현저히 높은 밀도를 보였다. 그러나 대장균은 모든 처리구에서 조사기간 동안 검출되지 않았다. 신선편이 양파의 표면 색도값($L^*$, $a^*$, $b^*$)은 포장방법이나 저장온도에 따른 차이는 없었으며, 다만 PE/PP에 진공 포장하여 $10^{\circ}C$에 저장 했을 때 저장 5일부터 17일까지 다른 처리구보다 현저히 높은 색차값(${\Delta}E$)을 나타내었다(p<0.05). 신선편이 양파의 산도는 포장방법 및 저장온도에 따른 영향은 없었으며, pH는 PE/PP 필름에 진공 포장하여 $10^{\circ}C$에 저장했을 때 저장시간이 지나면서 점차 증가하는 경향이었다. PE 필름에 신선편이 양파를 밀봉하고 포장 내 기체조성 변화를 조사한 결과 저장온도 간에 현저한 차이를 나타내었으며, $4^{\circ}C$에서 보다 $10^{\circ}C$에서 높은 $CO_2$ 농도와 낮은 $O_2$ 농도를 나타내었다(p<0.05). 신선편이 양파의 외관 품질은 저장시간이 지나면서 점차 낮게 평가되었으며, 특히 저장 13일 이후부터는 포장방법 및 저장온도에 따라 현저한 차이를 보였다(p<0.05). 신선편이 양파의 관능적 품질은 저장온도에 보다 큰 영향을 받았으며, 동일한 저장 온도에서는 PE 필름에 밀봉한 양파보다는 PE/PP 필름에 진공 포장한 신선편이 양파의 품질이 더 양호하였다. 결과를 종합해보면 신선편이 양파를 PE/PP 필름에 진공 포장하고 $4^{\circ}C$에 저장 유통하는 것이 유통기한 연장 및 품질유지에 가장 효과적인 것으로 판단된다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
• /
• pp.289-289
• /
• 2013

While there are plenty of studies on synthesizing semiconducting germanium nanowires (Ge NWs) by vapor-liquid-solid (VLS) process, it is difficult to inject dopants into them with uniform dopants distribution due to vapor-solid (VS) deposition. In particular, as precursors and dopants such as germane ($GeH_4$), phosphine ($PH_3$) or diborane ($B_2H_6$) incorporate through sidewall of nanowire, it is hard to obtain the structural and electrical uniformity of Ge NWs. Moreover, the drastic tapered structure of Ge NWs is observed when it is synthesized at high temperature over $400^{\circ}C$ because of excessive VS deposition. In 2006, Emanuel Tutuc et al. demonstrated Ge NW pn junction using p-type shell as depleted layer. However, it could not be prevented from undesirable VS deposition and it still kept the tapered structures of Ge NWs as a result. Herein, we adopt $C_2H_2$ gas in order to passivate Ge NWs with carbon sheath, which makes the entire Ge NWs uniform at even higher temperature over $450^{\circ}C$. We can also synthesize non-tapered and uniformly doped Ge NWs, restricting incorporation of excess germanium on the surface. The Ge NWs with carbon sheath are grown via VLS process on a $Si/SiO_2$ substrate coated 2 nm Au film. Thin Au film is thermally evaporated on a $Si/SiO_2$ substrate. The NW is grown flowing $GeH_4$, HCl, $C_2H_2$ and PH3 for n-type, $B_2H_6$ for p-type at a total pressure of 15 Torr and temperatures of $480{\sim}500^{\circ}C$. Scanning electron microscopy (SEM) reveals clear surface of the Ge NWs synthesized at $500^{\circ}C$. Raman spectroscopy peaked at about ~300 $cm^{-1}$ indicates it is comprised of single crystalline germanium in the core of Ge NWs and it is proved to be covered by thin amorphous carbon by two peaks of 1330 $cm^{-1}$ (D-band) and 1590 $cm^{-1}$ (G-band). Furthermore, the electrical performances of Ge NWs doped with boron and phosphorus are measured by field effect transistor (FET) and they shows typical curves of p-type and n-type FET. It is expected to have general potentials for development of logic devices and solar cells using p-type and n-type Ge NWs with carbon sheath.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
• /
• pp.278-280
• /
• 1994

The purpose of this paper is to describe an application of plasma polymerized thin film as an electron beam resist. Plasma polymerized thin film was prepared using an interelectrod inductively coupled gas-flow-type reactor. Styrene was chosen as the monomer to be used. This thin films were also delineated by the electron-beam apparatus and the pattern in the resist was developed with RIE and plasma polymerized apparatus. The effect of charge of pressure on growth rate and etching rate of the thin films were studied. The molecular structure of thin film was investigated by FT-IR and then was discussed in relation to its quality as a resist.

• 한국자기학회:학술대회 개요집
• /
• 한국자기학회 2002년도 동계연구발표회 논문개요집
• /
• pp.214-215
• /
• 2002

High saturation magnetization (B$\_$s/) and excellent high frequency characteristics of magnetic thin films has been recognized as the most important requirement for further miniaturization and higher frequency operation in magnetic devices, such as magnetic heads and magnetic sensors. Up to now, Fe-X-N (X =Ti, Hf, and Al etc.) films with B$\_$s/ of 15 ∼ 19 kG and coercivity (H$\_$c/) of 0.5 ∼ 5.0 Oe have been successfully fabricated and proven to satisfy various requirements as a potential candidate for thin film head materials. (omitted)