Temperature-dependent Raman investigation of CuInS2 with mixed phases of chalcopyrite and CuAu
Temperature-dependent Raman investigation of CuInS2 with mixed phases of chalcopyrite and CuAu
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黄铜矿和 CuAu 混合相 CuInS2 的温度依赖性拉曼研究
DOI：
10.1002/pssa.201127262
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发表时间：
2011-12-01
影响因子：
2
通讯作者：
Wang, Deliang
中科院分区：
文献类型：
--
作者：
Wu, Kunjie;Wang, Deliang
采用共蒸发Cu？在合金膜中。详细的温度依赖的拉曼散射进行了CuInS 2薄膜在温度范围从83至693？K. CH和CA A1模的拉曼位移随温度的变化符合Ridley模型。温度升高时的拉曼频率软化可以用热膨胀和三/四声子非谐过程的综合贡献来描述。不同的拉曼线宽展宽行为观察到的CH和CA A1模式在温度低于类似400？K.对于CH-A1模，多声子非谐过程拟合与实验线宽数据吻合较好，而对于CA-A1模，多声子非谐过程拟合只能在高温下与实验线宽数据吻合较好。在低温下，CA A1模式的不寻常的温度依赖性增宽被认为是由CH/CA相边界处的声子散射引起的，该相边界包括嵌入在CH微晶中的纳米尺寸的CA域。发现CA A1和CH A1模的强度比（I（CA）/I（CH））比CH A1线宽更能反映不同温度下CH的结晶度。根据I（CA）/I（CH）的温度依赖性，表明在试验过程中没有发生相变。
CuInS2 thin films with mixed phases of chalcopyrite (CH) and CuAu (CA) were prepared by using sulfurization of co-evaporated Cu?In alloy films. Detailed temperature-dependent Raman scattering was carried out on the CuInS2 films at temperatures ranging from 83 to 693?K. The temperature dependences of Raman shifts were well fitted by using the Ridley model for both the CH and the CA A1 modes. The Raman frequency softening upon increasing the sample temperature could be well described by the combined contributions of both thermal expansion and three/four-phonon anharmonic processes. Different Raman linewidths broadening behaviors were observed for the CH and CA A1 modes at temperature below similar to 400?K. For the CH A1 mode, the fitting using multiple-phonon anharmonic process matched the experimental linewidth data very well, while for the CA A1 mode, the multiple-phonon fitting could only match the experimental linewidth data at high temperature. At low temperature, the unusual temperature-dependent broadening of the CA A1 mode was believed to arise from the phonon scattering at the CH/CA phase boundary, which encompassed the nano-sized CA domains embedded in the CH crystallite. It was found that the intensity ratio between CA A1 and CH A1 modes (I(CA)/I(CH)) was more reliable in assessment of CH crystallinity at different temperature than CH A1 linewidth. According to the temperature dependence of I(CA)/I(CH), it showed that no phase transformation took place during the test.