非晶硒合金膜载流子特性研究  

TRANSPORT PROPERTIES OF AMORPHOUS SELENIUM ALLOY FILM

作　　者：徐向晏[1] 牛憨笨[1] 王云程[1] 

机构地区：[1]中国科学院西安光学精密机械研究所光电子部,西安710068

出　　处：《光子学报》1999年第10期895-900,共6页Acta Photonica Sinica

摘　　要：在X射线医学成象和无损检测方面，非晶硒现在被认为是最有前途的探测材料之一，其我流子特性对应用至关重要．本文描述了非晶硒（掺砷）合金材料的制备和合金膜的真空蒸镀制备方法，并用滚越时间方法测量了载流于的漂移迁移率和寿命．讨论了一些对非晶硒合金膜性能有重要影响的因素．实验表明，制备方法对非晶硒合金膜的性能有显著影响．可以看到，在低电场下被陷讲捕获的我流子形成的空间电荷对测量我流永寿命和对光的敏感度有很大影响·实验得到了良好的结果，在10Wpm场强下，空穴迁移长度约150o尸m，电子迁移长度约1200μm．该结果表明，可以用几百微米厚的非晶硒合金膜作为X射线探测或成象的光电导接受器．Amorphous selenium (a-Se ) is now considered as one of the mostpromising X-ray detectorin medlcal imaging and non-destructive diagnostics. Its transport properties of carriers are very criticalfor such .pplications . The .a-Se alloy material (doped with about 0-.5at. % As) is properly prepared,and alloy films are deposited by vacuum evaporation. The transport properties of hole and electron aremeasured by timemof-flight technique- Some factors,which affect the properties of a-Se,are discussed.Attention has been paid to trapped charges,which would significantly affect the sensitivity and makelifetime ineasurement complex,probably cause wrong results at low field. The results show that driftlength about 1500μm for hole and 1200μm for electron at 10V/μm field can be reached. This indicatesthat several hundred microns a Se alloy film can be used as X-ray detector.

关 键 词：非晶硒 渡越时间 漂移迁移率 迁移长度 载流子 

分 类 号：TN304.13[电子电信—物理电子学]