• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.1332_1333
• /
• 2009

The electrical properties of an inorganic/organic heterojunction has been investigated by spin coating the p-type polymer poly(3,4 ethylenedioxythiophene) : poly(styrenesulfonate) (PEDOT:PSS) on an n-type gallium doping zinc oxide (GZO) film. Current-voltage (I-V) characteristics of the fabricated heterojunction diodes have a good rectifying characteristics. The barrier height is calculated 0.8 eV.

• ETRI Journal
• /
• v.39 no.5
• /
• pp.746-755
• /
• 2017

In this paper, an electrostatic discharge (ESD) protection circuit is designed for use as a 12 V power clamp by using a parasitic-diode-triggered silicon controlled rectifier. The breakdown voltage and trigger voltage ($V_t$) of the proposed ESD protection circuit are improved by varying the length between the n-well and the p-well, and by adding $n^+/p^+$ floating regions. Moreover, the holding voltage ($V_h$) is improved by using segmented technology. The proposed circuit was fabricated using a $0.18-{\mu}m$ bipolar-CMOS-DMOS process with a width of $100{\mu}m$. The electrical characteristics and robustness of the proposed ESD circuit were analyzed using transmission line pulse measurements and an ESD pulse generator. The electrical characteristics of the proposed circuit were also analyzed at high temperature (300 K to 500 K) to verify thermal performance. After optimization, the $V_t$ of the proposed circuit increased from 14 V to 27.8 V, and $V_h$ increased from 5.3 V to 13.6 V. The proposed circuit exhibited good robustness characteristics, enduring human-body-model surges at 7.4 kV and machine-model surges at 450 V.

• Tunnel and Underground Space
• /
• v.18 no.5
• /
• pp.386-392
• /
• 2008

Recently, an earthquake-resistant has become essential to the large-scale structures at Gyeonggi and Gyeongsangnam province in Korea, but it is generally compared the measured data with foreign references because of the lack of the research data. It will be presented the characteristics of suitable dynamic elastic modulus in Korean geology, which characteristics are characterized the seismic wave velocities($V_p,\;V_s$) and correlation with dynamic elastic modulus($E_d,\;G_d\;K_d$) by each rock type of Korean granite, because it is very different between the values of foreign references and Korean geological characteristics.

• Journal of Korean Society on Water Environment
• /
• v.23 no.1
• /
• pp.122-130
• /
• 2007

This study was conducted to evaluate water treatment characteristics according to vegetated wetland(V) and open water(O) arrangements in free water surface constructed wetland. Three pilot-scale wetlands, V-V, O-V and V-O, were built and operated. $BOD_5$ was a slightly reduced at all the arrangements because the influent concentration was so low as background concentration of constructed wetlands. While T-N and T-P removal efficiency showed higher than 50% for all cases. The O-V arrangement showed the highest removal efficiency: 20% for $BOD_5$, 56% for SS, 59% for T-N and 72% for T-P. Effluent concentration of the O-V were significantly low compared with those from the V-O. O-V arrangement would be beneficial in the light of pollutant removal efficiency as well as construction cost.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.19 no.2
• /
• pp.126-129
• /
• 2006

We investigated an optimized condition of the capacitor threshold voltage implantation(capacitor $V_T$ Implant) in planar P-MOS DRAM Cell. Several samples with different condition of the capacitor $V_T$ Implant were prepared. It appeared that for the capacitor $V_T$ Implant of $BF_2\;2.0{\times}l0^{13}\;cm^{-2}$ 15 KeV, refresh time is three times larger than that of the sample, in which capacitor $V_T$ Implant is in $BF_2\;1.0{\times}l0^{13}\;cm^{-2}$ 15 KeV. Raphael simulation revealed that the lowed maximum electric field and lowed minimum depletion capacitance ($C_{MIN}$) under the capacitor resulted in well refresh characteristics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.95-95
• /
• 2008

본 연구에서는 SiGe p-MOSFET을 제작하여 I-V 특성과 게이트 길이, $V_D$, $V_G$의 변화에 따른 저주파 노이즈특성을 측정하였다. Si 기판위에 성장한 $Si_{0.88}Ge_{0.12}$으로 제작된 SiGe p-MOSFET의 채널은 게이트 산화막과 20nm 정도의 Si Spacer 층으로 분리되어 있다. 게이트 산화막은 열산화에 의해 70$\AA$으로 성장되었고, 게이트 폭은 $25{\mu}m$, 게이트와 소스/드레인 사이의 거리는 2.5때로 제작되었다. 제작된 SiGe p-MOSFET은 빠른 동작 특성, 선형성, 저주파 노이즈 특성이 우수하였다. 제작된 SiGe p-MOSFET의 ESD 에 대한 소자의 신뢰성과 내성을 연구하기 위하여 SiGe P-MOSFET에 ESD를 lkV에서 8kV까지 lkV 간격으로 가한 후, SiGe P-MOSFET의 I-V 특성과 게이트 길이, $V_D$, $V_G$의 변화에 따른 저주파 노이즈특성 변화를 분석 비교하였다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.27 no.8
• /
• pp.497-500
• /
• 2014

In this paper, we analyze electrical characteristics of n/p-pillar layer according to trench angle which is the most important characteristics of SJ MOSFET and core process. Because research target is 600 V class SJ MOSFET, so conclusively trench angle deduced 89.5 degree to implement the breakdown voltage 750 V with 30% margin rate. we found that on resistance is $22mohm{\cdot}cm^2$ and threshold voltage is 3.5 V. Moreover, depletion layer of electric field distribution also uniformly distributes.

• Journal of IKEEE
• /
• v.26 no.2
• /
• pp.329-332
• /
• 2022

In this paper, retention characteristics of lateral charge migration according to parameters of 3D NAND flash memory to which ferroelectric (HfO₂) structure is applied and ∆V_th were analyzed. The larger the P_s, the greater maximum polarization possible in ferroelectric during Programming. Therefore, the initial V_th increases by about 1.04V difference at P_s 70µC/cm² than at P_s 25µC/cm². Also, electrons trapped after the Program operation causes lateral charge migration over time. Since ferroelectric maintains polarization without applying voltage to the gate after Programming, regardless of P_s value, polarization increases as P_r increases and the ∆V_th due to lateral charge migration becomes smaller by about 1.54V difference at P_r 50µC/cm² than P_r 5µC/cm².

• Journal of the East Asian Society of Dietary Life
• /
• v.27 no.3
• /
• pp.341-347
• /
• 2017

This study was carried out to investigate the characteristics and Vitamin $K_2$ (MK-7) productivity of Cheonggukjang fermented by Bacillus subtilis SRCM100757 depending on the inoculum concentration 0.5% (v/w), 1% (v/w) and 2% (v/w). The lowest moisture content and water activity were $53.7{\pm}0.6%$ and $8.39{\pm}0.09$ after fermentation for 72 hours at 2% (v/w). pH slowly became alkalized during fermentation, but there was no significant difference. Amino nitrogen content increased with time and the highest content was $580.8{\pm}1.9mg%$ after fermentation for 72 hours at 2% (v/w). Lightness (L value) and yellowness (b value) decreased with time, whereas redness (a value) hardly changed. MK-7 contents increased with time at each inoculum concentration. The highest content was $20.47{\pm}1.53$ after fermeatation for 72 hours at 2%(v/w) and there were no significant differences between 1%(v/w) and 2%(v/w) inoculum concentrations.

• Laser Solutions
• /
• v.8 no.3
• /
• pp.5-10
• /
• 2005

[ $InxGa_{1-x}P/GaAs$ ] structures were grown by chemical beam epitaxy(CBE), Pure phosphine($PH_3$) gases were used as group V sources. for the group III sources, TEGa, TmIn were used. $InxGa_{1-x}P$ epilayer was grown on SI-GaAs substrate and has a 1-${\mu}m$ thick. We have investigated the characteristics of $InxGa_{1-x}P$ by the photoreflectance(PR) spectroscopy, The PR spectrum of $InxGa_{1-x}P$ shows third-derivative feature whose Peaks Provide energy gap. The energy gap of $InxGa_{1-x}P$ has deduced composition x. From temperature dependance of PR spectra, temperature coefficient is $dEg/dT=-3.773{\times}10^{-4}$ eV/K, and Varshni coefficients $\alpha$ and $\beta$ values obtained $4{\times}10^4$ eV/K and 267 K respectively. Also, interaction $\alpha$B was 19.4 meV using the Bose-Einstein temperature relation, and $\Theta$ value related the average phonon frequency were 101.4 K. In particular, shoulder peak related to defects observed in PR signal that measured in temperature 82 K.