• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.37-40
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• 2000

This paper has been studied on characteristics of organic light-emitting device with various cathode materials. These catode materials were Al：Li(5%), Al, Cu, CsF/Al. And in these devices, HTL(hole transfer layer) was TPD and EML(emitting layer) was Alq$\sub$3/. We studied the I-V characteristics for each device. And then, the turn-on voltage of device for Al-Li(5%), Al, Cu, CsF/Al cathode were 7, 9, 13, 3V respectively. So, the CsF/Al cathode is superior to other cathode materials for I-V characteristics.

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.180-181
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• 2003

Czochralski 방법으로 KMg $F_3$：S $m^{2+}$ 결정을 성장시키고 고 분해 레이저 분광법을 이용하여, 형광특성을 조사하였다. S $m^{2+}$ 이온이 KMg $F_3$ 결정에서 $C_{4v}$, $C_{2v}$, $C_{3v}$ 및 $O_{h}$ 형광 방출 사이트를 가진다는 것을 확인하였고, 아울러 각 사이트의 에너지 준위를 구하였다. 구하였다.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.35T no.1
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• pp.48-58
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• 1998

For the purpose of designing novel capacitance pressure sensor, several effects on sensitivity such as parasitic capacitance effects, temperature/thermal drift and leakage current have to be eleiminated. This paper proposed the experimental studies on frequency compensation method by electronic circuit technique, C-V converting method with switched capacitor and C-F converting method with schmitt trigger circuit. The third interface circuit by frequency compensation method is composed to eliminate the drift and leakage component by comparision sensing frequency with reference frequency. The signal transmission is realized by digital signal to minimize the influence of noise and high resolution is obtained by means of increasing the number of digital bits. In the fabricated high performance C-V interface, the offset voltage was not appeared, and in case of voltage source, 4.0V, feed back capacitance, 10㎊, the pressure, 0~10 ㎪, the sensitivity of C-V converter is 28 ㎷/㎪.V, the temperature drift characteristic, 0.051 %F.S./$^{\circ}C$ and C-F converter shows -6.6 Hz/pa, 0.078 %F.S./$^{\circ}C$ respectively, relatively good ones.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.8
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• pp.823-829
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• 2004

In this paper, non-self-aligned SiGe HBTs with ${f}_\tau$ and${f}_max $above 50 GHz have been fabricated using an RPCVD(Reduced Pressure Chemical Vapor Deposition) system for wireless applications. In the proposed structure, in-situ boron doped selective epitaxial growth(BDSEG) and TiSi$_2$ were used for the base electrode to reduce base resistance and in-situ phosphorus doped polysilicon was used for the emitter electrode to reduce emitter resistance. SiGe base profiles and collector design methodology to increase ${f}_\tau$ and${f}_max $ are discussed in detail. Two SiGe HBTs with the collector-emitter breakdown voltages ${BV}_CEO$ of 3 V and 6 V were fabricated using SIC(selective ion-implanted collector) implantation. Fabricated SiGe HBTs have a current gain of 265 ∼ 285 and Early voltage of 102 ∼ 120 V, respectively. For the $1\times{8}_\mu{m}^2$ emitter, a SiGe HBT with ${BV}_CEO$= 6 V shows a cut-off frequency, ${f}_\tau$of 24.3 GHz and a maximum oscillation frequency, ${f}_max $of 47.6 GHz at $I_c$of 3.7 mA and$V_CE$ of 4 V. A SiGe HBT with ${BV}_CEO$ = 3 V shows ${f}_\tau$of 50.8 GHz and ${f}_max $ of 52.2 GHz at $I_c$ of 14.7 mA and $V_CE$ of 2 V.

• New & Renewable Energy
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• v.3 no.4
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• pp.63-68
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• 2007

유리를 기판으로 하는 superstrate pin 비정질 실리콘 태양전진에서 전면 투명전도막(TCO)과 p-층의 계면은 태양전지 변환효율에 큰 영향을 미친다. 면투명전도막(TCO)으로 현재 일반적으로 사용되는 ZnO:Al는 $SnO_2:F$보다 전기, 광학적으로 우수하고, 안개율 (Haze)높으며, 수소 플라즈마에서 안정성이 높은 특징을 갖고 있다. 그래서 박막 태양전지의 특성향상에 매우 유리하나, 태양전지로 제조했을 때, $SnO_2$보다 충진율(Fill Factor:F.F)과 $V_{oc}$가 감소한다는 단점을 가지고 있다. 본 실험실에서는 $SnO_2:F$dml F.F.가 72%이 나온 반면 ZnO:Al의 F.F은 68%에 그쳤다. 이들 원인을 분석하기 위해 TCO/p-layer의 전기적 특성을 알아 본 결과, $SnO_2:F$보다 ZnO:Al의 직렬저항이 높게 측정되었다. 이러한 결과를 바탕으로 p-layer에 $R=(H_2/SiH_4)=25$로 변화, p ${\mu}c$-Si:H/p a-SiC:H로 p-layer 이중 증착, p-layer의 boron doping 농도를 증가시키는 실험을 하였다. 직렬저항이 가장 낮았던 p ${\mu}c$-Si:H/p a-SiC:H 인 p-layer 이중 증착에서 $V_{oc}$는 0.95V F.F는 70%이상이 나왔다. 이들 각 p층의 $E_a$(Activiation Energy)를 구해본 결과, ${\mu}c$-Si:H의 Ea 가 가장 낮은 것을 관찰 할 수 있었다.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.435-438
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• 2000

Crude oil-degrading microorganisms, Acinetobacter sp. A132, Pseudomonas aeruginosa F722, and Acinetobacter calcoaceticus OM1 were isolated from soil and sea. The optimal temperature of strain A132 and strain F722 on growth isolated from soil was $35^{\circ}C$ both, and also their growth were optimized at pH 8 and 9, respectively. The growth of the strains, A132 and F722, showed that crude oil of 2% (w/v) in culture broth in which crude oil was used as carbon and energy sources appeared to be an optimum. Optimal culture conditions of strain OM1 were different from those of the soil microorganisms except for temperature. The growth of strain OM1 was optimized at pH 7 and crude oil of 3.0% (w/v). The degradability to crude oil by strain A132 showed maximum $5.49g/\;l\;{\cdot}\;day$ under the conditions of $25^{\circ}C$, NaCl of 1.0% (w/v), and crude oil of 2.0% (w/v). The highest degradability of strain F722 to crude oil was $1.19g/\;l\;{\cdot}\;day$ under the culture conditions at $35^{\circ}C$, NaCl 1.0% (w/v), and crude oil of 2.0% (w/v). The degradation characteristics of kerosene $(nC_9-nC_{20})$ and diesel $(nC_9-nC_{28})$ by strain OM1, and F722 were analyzed by gas chromatography. Strain OM1 degraded more than 95% of kerosene and 75% of diesel for 7 days cultivation. Strain F722 showed degradation of more than 80% to kerosene in 10 days.

• Analytical Science and Technology
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• v.26 no.1
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• pp.51-60
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• 2013

The geometrical parameters, vibrational frequencies, and adiabatic electron affinities (AEAs) for c-$C_nF_{2n}$ (n=8, 9) and $C_{10}F_{18}$ (perfluorodecalin) have been investigated using various quantum mechanical techniques. The possible structures for the neutrals and anions of c-PFA are fully optimized and electron affinities are predicted using energy difference between the neutral and anion. The harmonic vibrational frequencies are also determined and zero-point vibrational energies (ZPVEs) are considered for the better prediction of the electron affinities. The electron affinities are predicted to be 1.18 eV for c-$C_8F_{16}$ (ortho), 1.37 eV for c-$C_9F_{18}$, and 1.38 eV for $C_{10}F_{18}$ (perfluorodecalin) at the MP2 level of theory after ZPVE correction.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1999.05a
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• pp.14-15
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• 1999

• Electrical & Electronic Materials
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• v.9 no.3
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• pp.251-258
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• 1996

Sol-Gel derived ferroelectric Pb(Z $r_{0.52}$ $Ti_{0.48}$) $O_{3}$ thin films have been fabricated on Pt/Ti/ $SiO_{2}$/Si substrate. Two kinds of fast annealing methods, F-I (six times of intermediate and final annealing) and F-II(one final annealing after six times of intermediate annealing) were used for preparation of multi-coated PZT thin films. As the annealing temperature was increased, high capacitance could be obtained, for instance, 2700.angs.-thick PZT thin film annealed at 680.deg. C had a capacitance value of approximately 20nF at 1kHz. In addition, it is found that the dielectric constant is a function of the perovskite phase fraction. In case of F-I method, PZT thin film had a remanent polarization(Pr) of 8-15.mu.C/c $m^{2}$ and a coercive field( $E_{c}$) of 35-44kV/cm according to annealing temperature, whereas PZT film fabricated by F-II method had as high as 24-25.mu.C/c $m^{2}$ and 48-59kV/cm, respectively. As a result of measuring Curie temperature, PZT thin film had a range of 460-480.deg. C by F-I method and more or less higher range of 525-530.deg. C by F-II method, which implied that different microstructures could cause the different Curie temperature. Through I-V measurement, leakage current of PZT thin film fabricated by F-I and F-II methods was 64nA/c $m^{2}$ and 2.2.mu.A/c $m^{2}$ in the electric field of 100kV/cm, respectively.y.y.y.

• Journal of Sensor Science and Technology
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• v.3 no.2
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• pp.65-73
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• 1994

TO:F($SnO_{2}:F$) thin films were prepared by RF magnetron sputtering system. The dependence of their structural, electrical, and optical properties on deposition conditions such as substrate temperature, working pressure and power was studied. The optimum conditions of TO:F thin film are $SnF_{2}$ content of 15wt.% in target, RF power of 150W, substrate temperature of $150^{\circ}C$ and working pressure of 2mmTr. The resistivity and transmittance at 550nm in visible spectrum of the TO:F film deposited at optimum condition are $9{\times}10^{-4}{\Omega}{\cdot}cm$ and above 85%, respectively. For the films deposited from the target without $SnF_{2}$ and with 15wt.% $SnF_{2}$, the optical bandgaps calculated from the transmittance curves are 3.84 and 3.9eV, respectively. X-ray diffraction patterns showed that TO and TO:F films had tetragonal rutile structure with (101), (200) direction.