Optoelectronic and low temperature thermoelectric effects in the OVC n-CuIn3Se5 thin films
Optoelectronic and low temperature thermoelectric effects in the OVC n-CuIn3Se5 thin films
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DOI：
10.1002/pssa.201228193
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发表时间：
2012-11-01
影响因子：
2
通讯作者：
Philip, R. R.
中科院分区：
文献类型：
--
作者：
Jacob, R.;Geethu, R.;Philip, R. R.
研究了三元黄铜矿有序空位化合物（OVC） n-CuIn3Se5多晶薄膜的光电性能和低温热电效应。采用x射线衍射仪（XRD）、原子力显微镜（AFM）和x射线光电子能谱仪（XPS）对三源真空共蒸发法制备的薄膜进行了结构、形貌和成分的初步表征。通过光学和光电子测量获得了材料的带隙、载流子浓度和光敏性。热能对温度的依赖表现出非简并的半导体性质，在载流子密度和薄膜中的费米能级之间建立了玻尔兹曼统计关系。虽然在室温附近检测到电离杂质散射，但在较低温度下，由于声子阻力的贡献，薄膜的负热功率增强。热功率、霍尔系数和电导率测量允许态密度、载流子浓度、漂移速度和载流子有效质量与薄膜电导率的相关性。(C) 2012 WILEY-VCH Verlag GmbH & Co., KGaA, Weinheim
Optoelectronic properties and low temperature thermoelectric effects were studied on polycrystalline thin films of ternary chalcopyrite ordered vacancy compound (OVC) n-CuIn3Se5. The thin films prepared by three source vacuum co-evaporation method were preliminarily characterized structurally, morphologically, and compositionally by X-ray diffraction (XRD), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS), respectively. Optical and optoelectronic measurements were done to obtain the band gap, carrier concentration, and photosensitivity of the materials. Thermopower dependence on temperature exhibited a non-degenerate semiconductivity, establishing Boltzmann statistics relation between carrier density and Fermi level in the films. While ionized impurity scattering has been detected near room temperature, an enhanced negative thermopower due to contribution from phonon drag has been noticed toward lower temperature in the films. Thermopower together with Hall coefficient and conductivity measurements permitted the correlation of density of states, carrier concentration, drift velocity, and the effective mass of the carriers with the conductivity of the films. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim