指数掺杂GaAs光电阴极分辨力特性分析  

Resolution characteristic of exponential-doping GaAs photocathodes

作　　者：邹继军[1,2] 常本康[2] 杨智[2] 张益军[2] 乔建良[2] 

机构地区：[1]东华理工大学电子工程系,抚州344000 [2]南京理工大学电子工程与光电技术学院,南京210094

出　　处：《物理学报》2009年第8期5842-5846,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:60801036;60678043);江西省自然科学基金(批准号:2007GQS0412);江西省教育厅科技计划(批准号:GJJ08298)资助的课题~~

摘　　要：通过建立和求解指数掺杂阴极中电子所遵循的二维连续性方程,得到了透射式指数掺杂阴极的调制传递函数表达式,并利用该表达式对阴极分辨力特性进行了理论计算和分析.计算结果显示,与均匀掺杂相比,指数掺杂能较明显地提高阴极的分辨力.当空间频率f在100—400lp/mm范围时,分辨力的提高最为明显,如当f=200lp/mm时,分辨力一般可提高20%—50%.与量子效率的提高相同,指数掺杂阴极分辨力的提高也是内建电场作用的结果.The modulation transfer function （MTF） of transmission-mode exponential-doping photocathodes has been solved from the 2- dimensional continuity equations. According to the MTF equation, we calculated and analyzed the theoretical resolution characteristic of the exponential-doping photocathodes. The calculated results show that, compared with the uniform-doping photocathodes, the exponential-doping structure can increase the resolution of photocathodes evidently. For the spatial frequency franges between 100 and 400 lp/mm, the increase of resolution is more pronounced. Let f = 200 lp/mm, the resolution of exponential-doping photocathodes generally increases by 20%--50%. The resolution improvement of exponential-doping photoeathodes, as well as the quantum efficiency improvement, is also attributed to the built-in electric field.

关 键 词：指数掺杂 内建电场 分辨力 调制传递函数 

分 类 号：O462[理学—电子物理学]