温度梯度溶液法生长的Cr掺杂的ZnTe晶体的表征  

Characterization of Cr-doped ZnTe Crystals Grown by Temperature Gradient Solution Growth(TGSG)

作　　者：杨睿[1] 介万奇[1] 孙晓燕[1] 杨敏[1] 呼唤[1] 蔺云[1] 

机构地区：[1]西北工业大学材料学院,凝固技术国家重点实验室,西安710072

出　　处：《无机材料学报》2015年第4期401-407,共7页Journal of Inorganic Materials

基　　金：国家重点基础研究发展计划(973)(2011CB610406);国家自然科学基金(51202197);中国111引智计划(B08040);高等学校博士学科点专项科研基金(20116102120014)~~

摘　　要：以Cr Te作为掺杂源、以Te作为溶剂,用温度梯度溶液法生长了Cr掺杂的Zn Te晶锭。晶锭头部的晶粒尺寸较大(>10 mm×10 mm),且Te夹杂相较少。Te夹杂相的大小、形状和分布可以反映晶锭中的温场分布。晶锭的径向非对称温场导致富Te相沿径向非对称分布。Te夹杂相在温度梯度作用下的热迁移会导致其相互融合长大、变长。Te夹杂相也会在晶体中引入裂纹和空洞等缺陷。部分未被掺入Zn Te中的Cr Te富集于固液界面处,表明温度梯度溶液法生长晶体时具有一定的排杂作用。Cr掺杂的Zn Te晶体的电阻率(约1000?·cm)高于未掺杂的Zn Te(约300?·cm)。Cr掺杂晶体在约1750 nm处的吸收峰表明Cr2+离子被成功地掺入了Zn Te中。但是Cr掺杂后晶体的红外透过率降低,表明Cr掺杂引入了较多的缺陷。Cr-doped Zn Te ingot was grown by temperature gradient solution growth（TGSG）, using Cr Te and Te as dopant source and solvent, respectively. Single crystals in the head of the ingot have larger size of more than 10 mm× 10 mm and less Te inclusions. The size, shape and distribution of Te inclusions well reflect the thermal field distribution of the ingot. Radial asymmetric thermal field of the ingot leads to radial asymmetric distribution of Te inclusions. The thermal migration of Te inclusions under thermal gradient results in their merging, enlargement and enlongation. Defects such as cracks and voids can be introduced into Zn Te matrix by Te inclusions. Some excess amount of Cr Te is rejected by the advancing interface, which indicates that the present growth method has self purification effect. The resistivity of Cr-doped Zn Te（ about 1000 ？·cm） is slightly higher than that of Zn Te（about 300 ？·cm）. Cr-doped Zn Te exhibits an absorption centered at about 1750 nm, which means Cr2＋ ions are successfully incorporated into Zn Te. IR transmittance of Cr-doped Zn Te is lower than that of Zn Te, which can be attributed to defects caused by Cr doping.

关 键 词：Cr掺杂ZnTe 晶体生长 Te夹杂相 电学和光学性能 

分 类 号：TQ174[化学工程—陶瓷工业]