反射式NEA GaN光电阴极量子效率恢复研究  

Quantum efficiency recovery of reflection-mode NEA GaN photocathode

作　　者：乔建良[1,2] 常本康[1] 钱芸生[1] 杜晓晴[3] 王晓晖[1] 郭向阳[1] 

机构地区：[1]南京理工大学电子工程与光电技术学院,南京210094 [2]南阳理工学院电子与电气工程系,南阳473004 [3]重庆大学光电工程学院,重庆400030

出　　处：《物理学报》2011年第1期728-733,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:60871012;60701013);河南省教育厅自然科学研究计划项目(批准号:2010C510009)资助的课题~~

摘　　要：以反射式NEAGaN光电阴极充分激活、衰减以及补Cs后的量子效率曲线为依据,针对阴极量子效率的衰减规律和补Cs后的恢复状况,论述了NEAGaN光电阴极量子效率的衰减和恢复机理.经过重新Cs化处理,反射式NEAGaN光电阴极量子效率在240nm到300nm的短波区域恢复到激活后最好状态的94%以上,300nm到375nm的长波区域恢复到88%以上.结合反射式NEAGaN光电阴极衰减前后的表面势垒形状和反射式GaN光电阴极量子效率的计算公式,得到了量子效率曲线的衰减规律以及补Cs后的恢复状况与表面势垒形状改变之间的关系.In order to investigate the decay tendency and the recovery status of the quantum efficiency of reflection-mode NEA GaN photocathode,the quantum efficiency curves have been studied after the photocathode was fully activated,stored in system and supplemented with Cs. The quantum efficiency decay and recovery processes of reflection-mode NEA GaN photocathode were observed and the mechanism was discussed. The quantum efficiency value of reflection-mode NEA GaN photocathode can be recovered up to more than 94% of the best value in the shortwave region between 240nm and 300nm, and more than 88% in the long wave region between 300nm and 375nm after Cs supplement. Based on the changes of surface potential barrier profiles of the reflection-mode NEA GaN photocathode before and after the quantum efficiency degradation and the quantum yield formula,the decay characteristic and the recovery status of quantum efficiency curve after supplement with Cs have been related to the changes of surface barrier shapes.

关 键 词：反射式 NEA GAN光电阴极 量子效率 

分 类 号：O471.1[理学—半导体物理]