大面积AlN基CdZnTe厚膜探测材料与表面、界面问题

本项目将研究在AlN基底上生长高质量CdZnTe厚膜的机理和工艺。通过对CdZnTe/AlN界面的修饰，重点研究CdZnTe/AlN的界面控制方法及界面对厚膜缺陷、探测效率、能谱响应特性的影响，并探究CdZnTe/AlN结构的新效应。在CdZnTe厚膜生长工艺中，提出新的组分蒸气压控制工艺来调控厚膜中的组成，并研究组分蒸气压控制方法对厚膜中的缺陷形成的影响机制，进而改善厚膜中的缺陷浓度和分布；研究晶界对厚膜中关键缺陷的吸收机理、研究前端铝诱导晶化生长工艺对厚膜晶粒的影响机理、计算获取厚膜中相关缺陷的动力学数据，并据此实现对厚膜中晶界、Te反位和Cd空位等主要缺陷的数量和分布的调控；最后，研究具有不同界面和缺陷分布特征的厚膜的能谱响应特性，探明界面、缺陷对能谱响应特性的影响机理，为高质量、大面积AlN基CdZnTe厚膜探测材料的制备提供实验和理论依据。

This proposal focuses on the research of mechanism and technology of high quality CdZnTe thick films based on AlN substrates. By modifying the contact layers of AlN/CdZnTe, the interface controlling method and new effects of CdZnTe/AlN structure are studied and the influence of interface on defects, detection efficiency and spectral response characteristics of the thick films are discussed. In the research of growth process, the influence of vapor pressure on defects of CdZnTe thick films is studied and new control technology of component vapor pressure is proposed to improve the concentration and distribution of defects. Based on this, the controlling of the main defects such as grain boundary, Te inversion and Cd vacancy is realized. Finally, we will investigate the response characteristics of thick films with different interfaces and defect distributions and find out how interfaces and defects affect the spectrum response, providing an experimental and theoretical basis for the growth of large, high quality CdZnTe thick films on AIN substrates which could be used as high performance nuclear detector materials.