• Proceedings of the Materials Research Society of Korea Conference
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• 2002.11a
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• pp.119-119
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• 2002

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.8
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• pp.34-45
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• 1994

We studied threshold voltages and I-V characteristics. considering short channel effect of the fully depleted thin film n-channel SOI MOSFET. We presented a charge sharing model when the back surface of short channel shows accumulation depletion and inversion state respectively. A degree of charge sharing can be compared according to each of back-surface conditions. Mobility is not assumed as constant and besides bulk mobility both the mobility defined by acoustic phonon scattering and the mobility by surface roughness scattering are taken into consideration. I-V characteristics is then implemented by the mobility including vertical and parallel electric field. kThe validity of the model is proved with the 2-dimensional device simulation (MEDICI) and experimental results. The threshold voltage and charge sharing region controlled by source or drain reduced with increasing back gate voltage. The mobility is dependent upon scattering effect and electric field. so it has a strong influence on I-V characteristics.

• Textile Coloration and Finishing
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• v.6 no.2
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• pp.30-39
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• 1994

To study the printing behaviors of Polyester and cotton(P/C) fabrics printed with disperse and reactive dyes, the effects of alkalis on the fixation of reactive dyes and the alkali-stability of disperse dyes in various methods of fixation were examined. The anthraquinone disperse dyes which have diamino derivatives as substituents without hydroxy group, such as C.I. Disperse Violet 1(D.V.1), C.I. Disperse Violet 28(D.V.28) and C.I.Disperse Blue 60(D.B.60) showed good results of fixation without regard to the concentration of NaHCO$_3$. In case of high temperature steaming(HTS) and unsaturated steaming(US)/HTS, D.V. 1 was alkali-stable and effective for P/C printing. A good result was obtained with D.V.1 and C.I.Reactive Orange 13(R.O.13) paste of 4% $K_{2}CO_{3}$. It was found that the unfixed D.V.28 bearing chloro group can hinder the fixation of monochlorotriaxinyl reactive dyes, and D.B.60 made little stain on 100% cotton. In thermosol(Tm), the dye uptake of D.V.1 was not decreased so much, but those of D.V.28 and D.B.60 were greatly decreased.

• JSTS:Journal of Semiconductor Technology and Science
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• v.8 no.1
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• pp.40-45
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• 2008

We developed small molecular organic nonvolatile $4F^2$ memory cells using metal layer evaporation followed by $O_2$ plasma oxidation. Our memory cells sandwich an upper ${\alpha}$-NPD layer, Al nanocrystals surrounded by $Al_2O_3$, and a bottom ${\alpha}$-NPD layer between top and bottom electrodes. Their nonvolatile memory characteristics are excellent: the $V_{th},\;V_p$ (program), $V_e$ (erase), memory margin ($I_{on}/I_{off}$), data retention time, and erase and program endurance were 2.6 V, 5.3 V, 8.5 V, ${\approx}1.5{\times}10^2,\;1{\times}10^5s$, and $1{\times}10^3$ cycles, respectively. They also demonstrated symmetrical current versus voltage characteristics and a reversible erase and program process, indicating potential for terabit-level nonvolatile memory.

• Journal of the Korean Ceramic Society
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• v.22 no.3
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• pp.19-24
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• 1985

The phtoelectrochemical porperties of $Nb_2O_5$, $Sb_2O_3$ and $V_2O_5$ doped and pure $SrTiO_3$ ceramic electodes were investigated. Shapes of I-V and I-λ characteristics of the pure $SrTiO_3$ ceramic electrode are similar to those of SrTiO3 single crystal electorde ; the anodic current strats at -0.9V (vs. Ag/AgCI) in 1 N-NaOH aqueous solution and the photoresponse appears at a wavelength of about 390nm and the quantum efficiency is about 3.5% at wavelength of 390nm under 0.5V vs. Ag/AgCl. Photocurrents of $Nb_2O_5$, $Sb_2O_3$ and $V_2O_5$ doped electrodes and $V_2O_5$ doped ceramic electrode appears at wavelength of 390nm and 500nm respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.3
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• pp.105-110
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• 2003

The ZnSe epilayers were grown on the GaAs substrate by hot wall epitaxy. After the ZnSe epilayers treated in the vacuum-, Zn-, and Se-atmosphere, respectively, the defects of the epilayer were investigated by means of the low-temperature photoluminescence measurement. The dominant peaks at 2.7988 eV and 2.7937 eV obtained from the PL spectrum of the as-grown ZnSe epilayer were found to be consistent with the upper and the lower polariton peak of the exciton, $I_{2}$ ($D^{\circ}$, X), bounded to the neutral donor associated with the Se-vacancy. This donor-impurity binding energy was calculated to be 25.3 meV, The exciton peak, $I_{1}^{d}$ at 2.7812 eV was confirmed to be bound to the neutral acceptor corresponded with the Zn-vacancy. The $I_{1}^{d}$ peak was dominantly observed in the ZnSe/GaAs : Se epilayer treated in the Se-atmosphere. This Se-atmosphere treatment may convert the ZnSe/GaAs : Se epilayer into the p-type. The SA peak was found to be related to a complex donor like a $(V_{se}-V_{zn})-V_{zn}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.120-123
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• 2003

The ZnSe epilayers were grown on the GaAs substrate by hot wall epitaxy. After the ZnSe epilayers treated in the vacuum-, Zn-, and Se-atmosphere, respectively, the defects of the epilayer were investigated by means of the low-temperature photoluminescence measurement. The dominant peaks at 2.7988 eV and 2.7937 eV obtained from the PL spectrum of the as-grown ZnSe epilayer were found to be consistent with the upper and the lower polariton peak of the exciton, $I_2$ ($D^{\circ}$, X), bounded to the neutral donor associated with the Se-vacancy. This donor-impurity binding energy was calculated to be 25.3 meV. The exciton peak, $I_1^d$, at 2.7812 eV was confirmed to be bound to the neutral acceptor corresponded with the Zn-vacancy. The $I_1^d$ peak was dominantly observed in the ZnSe/GaAs:Se epilayer treated in the Se-atmosphere. This Se-atmosphere treatment may convert the ZnSe/GaAs:Se epilayer into the p-type. The SA peak was found to be related to a complex donor like a $(V_{Se}-V_{Zn})-V_{Zn}$.

• Journal of the Korean Chemical Society
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• v.29 no.4
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• pp.372-381
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• 1985

Oxo molybdenum (V) complexes of substituted 8-quinolinols were synthesized and characterized by means of the investigation of elemental analysis, infrared spectra, electron spectra, electric conductivity and mass spectrometry compared with oxo molybdenum (VI) complexes. Oxo molybdenum(V) complexes were nonelectrolyte and one strong band of stretching mode of molybdenum and terminal oxygen appeared approximately $940cm^{-1}$. Oxo molybdenum(VI) complexes gave two peaks corresponding molybdenum containing ions, a molecular ion (I) of a 2 : 1 (ligand : metal) chelate and a fragment ion (II) of a 1:1 chelate due to the loss of ligand radical from ion (I). Molybdenum(V) complexes were observed the fragment ion(II) of a 1 : 1 chelate partly. The electronic spectra corresponding to d-d transition and charge transfer transition were observed and interpreted.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.165-168
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• 2002

TLC(Thin Layer Chromatography) 는 제약산업이나 생화학 연구 그리고 여러 산업 현장에서 널리 이용되는 화학 분석 방법이다 . 본 연구에서는 적은 비용으로도 많은 양의 시료를 신속하게 분리할 수 있는 TLC를 이용하여 유기산인 젖산 (Lactic acid) 을 분리는 전개방법을 개발하였다 . 전개용매는 2 가지 용매 (1) nitroethane nitromethane : ethanol: water: I-propanol = 1 : 2 : 3 : 4 : 5 (v/v/v/v/v), (2) diisopropyl ether. formic acid. water = 90 : 7 : 3 (v/v/v) 를 사용하였다 . 발색시약은 A : bromocresol purple reagent I, B . bromocresol purple reagent II, C : bromocresol green-bromophenol blue-potassium permanganate reagent 를 사용하여 분석하는 방법을 개발하였다 $^6)$. 젖산의 분리는 silica gel TLC plate를 이용하는 경우 , 용매 (1) 에 발색시약 B를 사용했을 때 , 분리 확인이 가장 좋았다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.82-82
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• 2003

p-CdI $n_2$T $e_4$ 단결정을 Bridgeman법으로 3단 수직 전기로에서 성장하였다. 성장된 결정의 결정성은 X선 회절과 광발광 측정으로 조사하였다 막 성장된(as-grown) 결정과 여러 열처리 CdI $n_2$T $e_4$ 결정들의 광발광 스펙트럼 측정으로부터 CdI $n_2$T $e_4$:Cd 광발광에서는 중성 주개 bound 엑시톤 ( $D^{\circ}$,X)가 우세함을 발견하였고 반면에 CdI $n_2$T $e_4$:Cd 광발광에서는 중성 받개 bound 엑시톤 ( $A^{\circ}$,X)가 완전히 사라졌다. 더우기, CdI $n_2$T $e_4$:Te의 광발광 스펙트럼에서 중성 받개 bound 엑시톤 ( $A^{\circ}$,X) 발광은 막 성장된 CdI $n_2$T $e_4$결정에서처럼 우세하였다. 이러한 결과들은 ( $D^{\circ}$,X)가 주개로써 작용하는 $V_{Te}$ ,와 관련이 있고, ( $A^{\circ}$,X)는 받개로 작용하는 $V_{cd}$와 관련이 있음을 가리킨다. p-CdI $n_2$T $e_4$ 결정은 Cd 증기 분위기에서 열처리한 후에는 n형으로 type conversion이 된다는 것을 알았다. 중성 주개-받개 bound 엑시톤 ( $D^{\circ}$, $A^{\circ}$)과 이들의 TO 포논 복제의 발광은 $V_{Te}$ 나 C $d_{int}$와 같은 주개들과 $V_{cd}$ 또는 T $e_{int}$와 같은 받개들 사이의 상호 작용과 관련이 있다. 또한, CdI $n_2$T $e_4$에서 In은 안정된 결합의 형태로 있기 때문에 자연 결함의 형성에는 관련이 없음을 알았다 알았다았다았다