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Photocurrent Study on the Splitting of the Valence Band and Growth of $CdIn_2Te_4$ Single Crystal by Bridgman method (Bridgman법에 의해 성장된 $CdIn_2Te_4$ 단결정의 가전자 갈라짐에 대한 광전류 연구)

  • Baek, Seung-Nam;Hong, Kwang-Joon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07a
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    • pp.347-351
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    • 2003
  • A p-$CdIn_2Te_4$ single crystal has been grown by the Bridgman method without a seed crystal in a tree-stage vertical electric furnace. From photocurrent measurements, it was found that three peaks, A, B, and C, corresponded to an intrinsic transition due to the band-to-band transition from the valence band states ${\Gamma}_7(A),\;{\Gamma}_6(B),\;and\;{\Gamma}_7(C)$ to the conduction band state ${\Gamma}_6$, respectively. Also, the valence band splitting of the $CdIn_2Te_4$ crystal has been confirmed by photocurrent spectroscopy. The crystal field splitting and the spin orbit splitting were obtained to be 0.2360 and 0.1119 eV, respectively. Also, the temperature dependence of the band gap energy of the $CdIn_2Te_4$ crystal has been driven as the following equation of $E_g(T)\;=E_g(0)\;-\;(9.43\;{\times}\;10^{-3})T^2/(2676\;+\;T)$. In this equation, the Eg(0) was estimated to be 1.4750, 1.7110, and 1.8229 eV at the valence band state A, B, and C, respectively. The band gap energy of the p-$CdIn_2Te_4$ at room temperature was determined to be 1.2023 eV.

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Optical Properties of Cdlnsub 2Ssub 4 and Cdlnsub 2Ssub 4 : $CdIn_2S_4$$CdIn_2S_4 : Co^{2+}$Single Crystals ($CdIn_2S_4$$CdIn_2S_4 : Co^{2+}$ 단결정의 광학적 특성)

  • Choe, Seong-Hyu;Bang, Tae-Hwan;Kim, Hyeong-Gon
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.48 no.5
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    • pp.296-302
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    • 1999
  • $CdIn_2S_4 and CdIn_2S_4 : Co^{2+}$ singlecrystals of thenormal spinel structure were grown by the C.T.R. method. The optical energy band structure of these compounds had a indirect band gap at the fundamental optical absorption band edge. The direct and the indirect energy gaps are found to be 2.325 and2.179eV for $Cdln_2S_4$ , and 2.303 and 2.169eV for $CdIn_2S_4 and CdIn_2S_4 : Co^{2+}$ at 5K, respectivly. The fundamental absorption band edge of these single crystals shift to a shorter wavelength region with decreasing temperature, and the temperature dependence of the optical energy gaps in these compounds satisfy Varshni equation. The Varshni constants$\alpha and \beta$ of the direct energy gap are given by $13.39{\times}10_{-4}eV/K$ and 509 K for $Cdln_2S_4$ and $29.73{\times}10_{-4} eV/K$ and 1398K for $CdIn_2S_4 and CdIn_2S_4 : Co^{2+}$. The Varshni constants ${\alpha}and {\beta}$ of the indirect energy gap are given by 9.68${\times}10^{-4}$ eV/K 308K for $Cdln_2S_4$ and $13.33{\times}10_{-4}eV/K$ and 440K for $CdIn_2S_4 : Co^{2+}$ respectivly. The impurity optical absorption peaks due to cobalt dopant are observed in $CdIn_2S_4 : Co^{2+}$ single crystal. These impurity optical absorption peaks can be attributed to the electronic transitions between the split energy levels of $Co_{2+}$ ions located at $T_d$ symmetry site of $Cdln_2S_4$ host lattece.

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Influence on the Anti-cancer and Immune response improvement of Herbal-acupuncture with Asparagus cochinchinensis infusion solution put into Chung-wan(CV12) and Kwanwon(CV4) (중완(中脘) 및 관원(關元)에 시술한 천문동약침이 항암 및 면역작용에 미치는 영향)

  • Jang, Suk-geun;Kang, Jae-hui;Yim, Yun-kyoung;Lee, Hyun;Lee, Byung-ryul
    • Journal of Acupuncture Research
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    • v.20 no.5
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    • pp.159-171
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    • 2003
  • Objective: To study on the anti-cancer, anti-metastasis and immune response improvement effects of Herbal-acupuncture with Asparagus cochinchinensis infusion solution. Methods: we put into Chung-wan(CV12) and Kwanwon(CV4) of C57bl/6 which are corresponding to human body with Asparagus coc hinchinensis infusion solution. We observed the effect on the expres sion of MMP-9. the expression of cytokine gene, number of pulmon ary colony, histological analysis on tissue metastasis of lung and liver. the expression of cytokine gene on PBMC. the number of $CD3e^+/CD4^+$. $CD3e^+/CD8^+$, $NK^+$ cell. Results: The results were obtained as follows I) The effect on expression of MMP-9. the expression of cytokine gen e was inhibited significantly in all the sample groups. compared with control group. 2) In pulmonary colony, sample groups were decreased significantly, compared with control group. especially, the group put into Chung-wan(CV12) was decreased significantly. 3) Histological analysis of sample groups inhibited significantly in all th e sample groups compared with that control groups in both of lung and liver. especially, the group put into Chung-wan(CV12) was inhibited significantly. 4) The effect on cytokine gene expression on PBMC of all the sample groups were increased significantly, compared with control group. 5) In flow cytometry, $CD3e^+/CD4^+$ $CD3e^+/CD8^+$, $NK^+$ cell in sample groups were increased compared with control group.

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Photoluminescence of Nanocrystalline CdS Thin Films Prepared by Chemical Bath Deposition

  • Park, Wug-Dong
    • Transactions on Electrical and Electronic Materials
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    • v.11 no.4
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    • pp.170-173
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    • 2010
  • Nanocrystalline cadmium sulfide (CdS) thin films were prepared using chemical bath deposition in a solution bath containing $CdSO_4$, $SC(NH_2)_2$, and $NH_4OH$. The CdS thin films were investigated using X-ray diffraction (XRD), photoluminescence (PL), and Fourier transform infrared spectroscopy (FTIR). The as-deposited CdS thin film prepared at $80^{\circ}C$ for 60 min had a cubic phase with homogeneous and small grains. In the PL spectrum of the 2,900 A-thick CdS thin film, the broad red band around 1.7 eV and the broad high-energy band around 2.7 eV are attributed to the S vacancy and the band-to-band transition, respectively. As the deposition time increases to over 90 min, the PL intensity from the band-to-band transition significantly increases. The temperature dependence of the PL intensity for the CdS thin films was studied from 16 to 300 K. The $E_A$ and $E_B$ activation energies are obtained by fitting the temperature dependence of the PL intensity. The $E_A$ and $E_B$ are caused by the deep trap and shallow surface traps, respectively. From the FTIR analysis of the CdS thin films, a broad absorption band of the OH stretching vibration in the range $3,000-3,600\;cm^{-1}$ and the peak of the CN stretching vibration at $2,000\;cm^{-1}$ were found.

Growth and Characterization for $CdIn_2S_4/GaAs$ Epilayers ($CdIn_2S_4$ 에피레이어 성장과 특성)

  • Hong, Kwang-Joon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.239-242
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    • 2004
  • A stoichiometric mixture of evaporating materials for $CdIn_2S_4$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, $CdIn_2S_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by hot wall epitaxy(HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $420^{\circ}C$ respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of $CdIn_2S_4$ single crystal thin films measured from Hall effect by van der Pauw method are $9.01{\times}10^{16}\;cm^{-3}$ and $219\;cm^2/V{\cdot}s$ at 293 K, respectively. From the optical absorption measurement, the temperature dependence of energy band gap on $CdIn_2S_4$ single crystal thin films was found to be $E_g(T)\;=\;2.7116\;eV\;-\;(7.74{\times}10^{-4}\;eV)T^2/(T+434)$. After the as-grown $CdIn_2S_4$ single crystal thin films was annealed in Cd-, S-, and In-atmospheres, the origin of point defects of $CdIn_2S_4$ single crystal thin films has been investigated by the photoluminescence(PL) at 10 K.

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Fabrication of $Cu_2/CdS$ solar cell and its characteristics ($Cu_2/CdS$ 태양전지 제작 및 그 특성연구)

  • 유평렬;김현숙;이재윤;강창훈;박은옥;정태수;김택성;양동익;신영진
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.7 no.2
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    • pp.315-323
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    • 1997
  • The sing1e crystal of cadmium sulfide was grown by vertical sublimation method. The lattice constants of CdS single crystal by extrapolation method are $a_0=4.139\AA$ and $c_0=6.719\AA$, respectively. The $Cu_2$S/CdS solar cell was fabricated using the single crystal of cadmium sulfide and the CuCl solution. The light- to- dark JV cross over effect of the $Cu_2$S/CdS solar cell was measured after annealing for 2 minutes at $250^{\circ}C$ in air atmosphere. The values of Voc, Jsc, Vop, FF, and efficiency are 0.40 volt, $4.2mA/\textrm{cm}^2$, 0.31 volt, $3.8mA/\textrm{cm}^2$, 0.68 and 3.8 %, respectively. The spectral response of the solar cell shows the peaks at 498 nm (2.49 eV) and 585 nm (2.12 eV).

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Photocurrent study on the splitting of the valence band and growth of $CdGa_2Se_4$ single crystal thin film by hot wall epitaxy (Hot Wall epitaxy(HWE)법에 의한 $CdGa_2Se_4$ 단결정 박막의 성장과 가전자대 갈라짐에 대한 광전류 연구)

  • Park, Chang-Sun;Hong, Kwang-Joon
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.17 no.5
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    • pp.179-186
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    • 2007
  • Single crystal $CdGa_2Se_4$ layers were grown on a thoroughly etched semi-insulating GaAs(100) substrate at $420^{\circ}C$ with the hot wall epitaxy(HWE) system by evaporating the polycrystal source of $CdGa_2Se_4$ at $630^{\circ}C$. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of single crystal $CdGa_2Se_4$ thin films measured with Hall effect by van der Pauw method are $8.27{\times}10^{17}cm^{-3},\;345cm^2/V{\cdot}s$ at 293 K, respectively. The photocurrent and the absorption spectra of $CdGa_2Se_4/SI$(Semi-Insulated) GaAs(100) are measured ranging from 293 K to 10 K. The temperature dependence of the energy band gap of the $CdGa_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation $E_g(T)=2.6400eV-(7.721{\times}10^{-4}eV/K)T^2/(T+399K)$. Using the photocurrent spectra and the Hopfield quasicubic model, the crystal field energy(${\Delta}cr$) and the spin-orbit splitting energy(${\Delta}so$) far the valence band of the $CdGa_2Se_4$ have been estimated to be 106.5 meV and 418.9 meV at 10 K, respectively. The three photocurrent peaks observed at 10 K are ascribed to the $A_{1^-},\;B_{1^-},\;and\;C_{11}-exciton$ peaks.

A Study on the Effect of Herbal-acupuncture with Eucomiae Cortex Solution at Joksamni$(ST_{36})$ on Collagen-induced Arthritis (족삼리(足三里) 두충약침(杜沖藥鍼)이 Collagen-induced Arthritis에 미치는 영향)

  • Kang, Jae-Hui;Lee, Hyun
    • Journal of Acupuncture Research
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    • v.23 no.3
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    • pp.129-142
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    • 2006
  • Objectives : The purpose of this study is to observe the effects of Eucomiae Cortex herbal-acupuncture solution(EC-HAS) at Joksamni(ST36) on arthritis of mice induced by Collagen II. Methods : The author performed several experimental items. First, it is the cell survival rate of mice lung fibroblasts. Second, it is the incidence rate of arthritis and arthritis index of CIA. Third, it is the levels of IL-6, $TNF-{\alpha}$, $IFN-{\gamma}$, $IL-{\beta}$, IgG, IgM and anti-collagen II in serum and the level of IFN-y,$IFN-{\gamma}$/IL -4 ratio in CIA mouse spleen cell culture. Fourth, it is histological analysis of the mice joint. Fifth, it is expression ratio of $CD3e^+$ to $CD19^+$+ cell, $CD4^+$ to $CD8^+$ cell, $CD69^+/CD3e^+$/cells, $CD11a^+/CD19^+$/cells, $CD11b^+/Gr-1^+$ cells and $CD4^+/CD25^+$ cells. Results & Conclusion : 1. In the EC-HA, the incidence of arthritis and arthritis index were significantly decreased. 2. In EC-HA, the levels of IL-6, $IFN-{\gamma}$, $TNF-{\alpha}$, $IL-1{\beta}$, IgG, IgM and anti-collagen II in serum of CIA mice and the level of $IFN-{\gamma}$, IL-4, $IFN-{\gamma}$/lL-4 ratio in CIA mouse spleen cell culture were significantly decreased. 3. In the histological study, the cartilage destruction and synovial cell proliferation were decreased in the EC-HA, and the collagen fiber expressions in the EC-HA were similar with that of the Normal group. 4. In the EC-HA, the expression ratio of $CD3e^+$ to $CD19^+$ cell and $CD4^+$ to $CD8^+$ cell were similarly maintained as Normal group in lymph nodes, and $CD69^+/CD3e^+$ cells and $CD11a^+/CD19^+$ cells were decreased in lymph nodes, and $CD11b^+/Gr-1^+$ cells and $CD4^+/CD25^+$ cells were decreased in synovium. These results suggest that EC-HA at ST36 has an effect to control synovial cell proliferation and cartilage destruction in rheumatoid arthritis, and to be put to practical use in the future rheumatoid arthritis clinic.

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A Study on the Effect of Herbal-acupuncture with Mori Ramulus Solution at Joksamni(ST36) on Collagen-induced Arthritis (족삼리(足三里) 상지약침(桑枝藥鍼)이 Collagen-induced arthritis에 미치는 영향)

  • Jeong, Yeong-Don;Yim, Yun-Kyoung;Lee, Hyun
    • Journal of Acupuncture Research
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    • v.23 no.6
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    • pp.29-44
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    • 2006
  • Objectives : The purpose of this study is to observe the effects of Mori Ramulus herbal-acupuncture solution(MR-HAS) on arthritis of mice induced by Collagen II at Joksamni(ST36). Methods : The author performed several experimental items. First, it is the cell survival rate of mice lung fibroblasts. Second, it is the incidence rate of arthritis and arthritis index of CIA. Third, it is the levels of IL-6, $TNF-{\alpha}$, $IFN-{\gamma}$, $IL-1{\beta}$, IgG, IgM and anti-collagen II in serum and the level of $IFN-{\gamma}$, $IFN-{\gamma}/IL-4$ ratio in CIA mouse spleen cell culture. Fourth, it is histological analysis of the mice joint. Fifth, it is expression ratio of CD3e+ to CD19+ cell, CD4+ to CD8+ cell, CD69+/CD3e+ cells, CD11a+/CD19+ cells and CD11b+/Gr-l+ cells and CD4+/CD25+ cells. Results : 1. In the MR-HA, the incidence of arthritis and the arthritis index were significantly decreased. 2. In MR-HA, the levels of IL-6, $IFN-{\gamma}$, $TNF-{\alpha}$, $IL-1{\beta}$, IgG, IgM and anti-collagen II in serum of CIA mice and the level of $IFN-{\gamma}$, IL-4, $IFN-{\gamma}$, IL-4 ratio in CIA mouse spleen cell culture were significantly decreased. 3. In histology, the cartilage destruction and synovial cell proliferation were decreased in the MR-HA, and the collagen fiber expressions in the MR-HA were similar with that of the Normal group. 4. In the MR-HA, the expression ratio of CD3e+ to CD19+ cell and CD4+ to CD8+ cell were similarly maintained as Normal group in lymph nodes, and CD69+/CD3e+ cells and CD11a+/CD19+ cells were decreased in lymph nodes, and CD11b+/Gr-1+ cells and CD4+/CD25+ cells were decreased in synovium. Conclusion : These results suggest that MR-HA at ST36 has an effect to control synovial cell proliferation and cartilage destruction in rheumatoid arthritis, as well as prophylaxis is important to treat rheumatoid arthritis in clinic.

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A Study of Cu-doped CdS thin film by E-beam (E-beam 제작된 Cu-doped CdS 박막에 관한 연구)

  • Kim, Seong-Ku;Park, Gye-Choon;Jo, Jae-Cheol;Jung, Woon-Jo;Rye, Yong-Tek
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1992.11a
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    • pp.67-72
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    • 1992
  • In this paper, We prepared the thin film Cu-doped CdS Photovoltaic Cell, varying deposition condition by E-beam process and investigated its properties. After the Cu/CdS films were deposited on transparent ITO glass. We heat-treated to diffuse Cu atoms to CdS fi1m at 350[$^{\circ}C$]. With deposited Cu-doped CdS film. We investigated the electrical. optical. X-ray diffraction and junction property. We studied how to prepare the High conversion efficiency Solar cell window layer.

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