采用AIM-8800红外显微镜观察了CdGeAs2晶体的面扫描红外透过图像,分别在2.3~4μm、4~8μm和8~18μm三个波段对退火前后的CdGeAs2晶片红外透过率和面扫描红外透过图像进行了对比分析,研究了晶体的红外均匀性。结果表明,CdGeAs2晶体在多晶粉末包裹下经450℃退火150 h后,其红外透过率和红外透过均匀性都得到较大程度的改善,其中在2.3~4μm和4~8μm波段的改善效果尤为显著;分析了影响晶体红外透过率和均匀性的主要因素,探讨了改善晶体均匀性的可能途径。研究结果对于快速评判CdGeAs2晶片质量具有重要的实用价值。
The scanning infrared maps of CdGeAs2 wafers respectively at three bands 2.3-4 μm,4-8 μm and 8-18 μm were determined by an infrared microscopy mapping system.The infrared transmittance spectra and scanning infrared maps of the CdGeAs2 wafers were compared and analyzed respectively before and after annealing.The results showed the infrared transmittance and its uniformity of the wafers improved obviously after annealing under cover-up with CdGeAs2 polycrystalline powder at 450 ℃ for 150 h,and the improvements at bands 2.3-4 μm and 4-8 μm were significant especially.The main factors affecting the infrared transmittance were analyzed theoretically,and the possible ways to enhance the infrared transmittance uniformity were also discussed in this paper.The research results have important application value in evaluating the properties of crystal wafer.