摘要
报道了采用富 Cd原料的无籽晶垂直布里奇曼法生长高阻碲锌镉 Cd0 .8Zn0 .2 Te(CZT)单晶体的新工艺 ,对所生长的晶体作了 X射线衍射分析、红外透过率测试、光吸收截止波长测量及电学性能测试 .晶体在 4 4 0 0～ 4 5 0 cm- 1范围内的红外透过率达到 5 0 % ,截止吸收波长为 787.6 nm,带隙为 1.5 74 e V,室温电阻率达到 2× 10 1 0 Ω· cm ,已接近本征 Cd0 .8Zn0 .2 Te半导体的理论值 .用该晶体制作的核探测器在室温下对 2 4 1 Am和 1 0 9Cd放射源均有响应 ,并获得了比较好的 2 4 1 Am- 5 9.5 ke V吸收谱 .结果表明改进的方法是一种生长室温核辐射探测器应用的高阻
Cd 0.8 Zn 0.2 Te crystal 20mm in diameter and 50mm in length is grown from Cd rich starting materials by unseeded vertical Bridgeman method.The as grown crystal is characterized by using X ray diffraction,IR transmission microscopy and electric property measurement.It is found that the transmission of the crystal sample of 5mm in thickness is up to 50% in the range from 4400～450cm -1 ,the energy gap is 1 574eV and the resistivity is 2×10 10 Ω·cm.The detector that is made from the as grown crystal is sensitive to two kinds of 241 Am and 109 Cd radiant resources.The results mentioned above show that the modified method is a simple and efficient method for the growth of high resistivity CZT crystal for room nuclear radiation detectors.
基金
国家自然科学基金资助项目 (批准号 :5 9972 0 19)~~
关键词
单晶生长
性能观测
碲锌镉晶体
Cd 0 8 Zn 0 2 Te
crystal growth
Bridgeman method
room nuclear radiation detector
