降温速率对CdZnTe晶体内Te夹杂相的影响  

Effect of Cooling Rate on Te Inclusions in CdZnTe Crystal

作　　者：张涛[1] 闵嘉华[1] 梁小燕[1] 滕家琪[1] 时彬彬[1] 杨升[1] 张继军[1] 王林军[1] 

机构地区：[1]上海大学,上海200072

出　　处：《稀有金属材料与工程》2014年第10期2541-2544,共4页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(11275122);上海市科委重点项目(11530500200);上海市教育委员会科研创新项目(12ZZ096)

摘　　要：采用改进的垂直布里奇曼生长法生长CdZnTe（CZT）单晶。生长完成后,选取了10-60 K/h不同速率降温处理。采用红外透射显微镜和多道能谱仪分别测试不同降温速率的晶片内部Te夹杂相分布和能谱响应。结果表明,10-30K/h之间的慢速降温会导致晶体内部出现较大尺寸的Te夹杂（〉10μm）,40 K/h以上的快速降温所得到的晶体内部主要以小尺寸（〈10μm）为主。同时快速降温会导致晶体内部的Te夹杂浓度大量增加,并且降温速率越快,Te夹杂浓度越大。此外,降温速率过慢所得到晶片的能谱分辨率较差,但是降温速率过快也会影响到晶片的性能。40 K/h的降温速率所得到的晶片能谱性能较好,实验结果表明：大尺寸或者高浓度的Te夹杂都不利于能谱响应,保留一定浓度的小尺寸Te夹杂的晶体能谱性能较佳。CdZnTe（CZT） single crystals were grown by a modified Vertical Bridgman method.After the growth was completed,cooling treatment was carried out at different rates between 10~60 K/h.IR microscopy and multi-channel spectrometer were employed to analyze the Te inclusions distribution in the crystal and spectroscopy response of each CZT wafers with different cooling rate,respectively.The results show Te inclusions with relatively large size（10 〉μm） appeared inside the crystal when the cooling rate was between 10 K/h and 30 K/h,while the size of most Te inclusions was below 10 μm when the cooling rate was over 40 K/h.Besides,fast cooling would cause great increase of Te inclusions concentration,and the faster the cooling rate,the higher the concentration of Te inclusions.In addition,the energy resolution of crystal annealed at too low cooling rate was poor.Meanwhile,annealing at too high cooling rate would degenerate the crystal performance.It was also noted that when the cooling rate was 40 K/h,the property of energy spectrum was better with lower energy resolution.In conclusion,Te inclusions with large size or high concentration would degenerate the spectroscopy response of the crystal,while keeping some small Te inclusions（10〈 μm） may lead to better spectroscopy performance.

关 键 词：Te夹杂相 降温速率 CDZNTE 

分 类 号：O785[理学—晶体学]