CdZnTe像素探测器表面的氧离子刻蚀工艺

Atomic oxygen exposure process on CdZnTe pixel detector suface

本文报道了CdZnTe像素探测器电极的氧离子刻蚀工艺。通过I-V特性、PL谱以及XPS等实验结果分析了氧离子刻蚀对CdZnTe表面成分、缺陷以及漏电流的影响。研究结果表明,表面氧离子刻蚀在CdZnTe晶体表面形成了致密氧化层。刻蚀功率过大时,刻蚀过程中氧离子轰击会对CdZnTe晶体表面造成损伤,使表面漏电流急剧增大。减小刻蚀功率,延长刻蚀时间,可以增强刻蚀过程中的化学作用,减少CdZnTe晶片的表面氧化与损伤,使表面漏电流降低。

Atomic oxygen exposure process on CdZnTe pixel detector contact electrode were reported in this paper.Chemical composition,defects and leakage current of the surface after atomic oxygen exposure were studied using I-V measurements,PL spectrum and XPS etc.The results show that atomic oxygen exposure forms a densified oxide layer on the surface of CdZnTe.In high atomic oxygen bombardment,the atomic oxygen damages the surface of CdZnTe crystal,which increases surface leakage current.In low atomic oxygen bombardment,extending time of bombardment can enhance chemical reaction in the bombardment process so that this process decreases surface leakage current due to the reduction of surface damage.