埋入GaAs/AlAs周期反射层提高反射式负电子亲和势阴极效率的研究  

Enhancement of Photoelectron Emission Efficiency of Negative Electron Affinity GaAs Cathode by Embedded GaAs/AlAs Multilayer Reflector

作　　者：徐宏伟[1] 王鼎盛[1] 

机构地区：[1]中国科学院物理所表面物理实验室,北京100080

出　　处：《Journal of Semiconductors》1992年第11期675-682,共8页半导体学报（英文版）

摘　　要：本文提出了在高掺杂反射式负电子亲和势 GaAs光阴极材料的活性层下埋入 GaAs/AlAs周期反射层,提高光的利用率,同时在界面附近引入电子势垒,提高光电子发射效率.文中对周期反射层的反射性能进行了设计和计算,并计算了埋入GaAs/AlAs周期反射层后的光电子发射效率.讨论了埋入 GaAs/AlAs周期反射层后最佳活性层厚度的选取-指出了对于扩散长度较短的材料,通过埋入周期反射层,能用较薄的活性层达到甚至超过无限厚活性层材料的极限效率.最后对光电发射实验的初步结果进行了讨论.Because usual negative electron affinity (NEA) GaAs photocathodes are highly doped andthus have short minority carrier diffusion length, a GaAs/AlAs multilayer reflector under the ac-tive layer will enhance the quantum yield by increasing the photoexcitation in the effective re-gion of the photocathode and introducing an elecrron barrier at the interface. The design andmeasuremem of the characteristic of the multilayer reflector were made and photoelectron emis-sion yields were calculated for the structures with GaAs/AlAs multilayer reflecrors. The opti-mum design parameters for the active layer thickness and initial photoemission measurements arediscussed.

关 键 词：阴极 电子亲和势 

分 类 号：TN103[电子电信—物理电子学]