表面势垒对梯度掺杂GaN光电阴极电子逸出几率的影响  

Influence of Surface Barrier on Electron Escape Probability of Gradient-doping GaN Photocathode

作　　者：王洪刚[1,2] 钱芸生[1] 杜玉杰[1] 任玲[1] 徐源[1] 

机构地区：[1]南京理工大学电子工程与光电技术学院,江苏南京210094 [2]鲁东大学信息与电气工程学院,山东烟台264025

出　　处：《计算物理》2013年第5期739-744,共6页Chinese Journal of Computational Physics

基　　金：国家自然科学基金(61171042)资助项目

摘　　要：研究表面势垒对梯度掺杂GaN光电阴极电子逸出几率的影响.计算梯度掺杂透射式GaN光电阴极的电子能量分布及逸出几率,结果显示梯度掺杂与均匀掺杂相比,可以获得更大的电子逸出几率;I势垒对电子逸出几率的影响显著,而II势垒影响较小.利用GaN光电阴极多信息量测试系统,测试两种GaN阴极样品的光电流.实验结果表明,梯度掺杂GaN样品比均匀掺杂电子逸出几率更大;单独进行Cs激活形成的I势垒对电子逸出几率有显著影响,而Cs/O共同激活形成的II势垒对其影响较小.Influence of surface potential barrier on escape probability of gradient-doping negative electron affinity （NEA） GaN photocathode was studied. Electron energy distribution and escape probability are calculated and compared with those of uniform-doping GaN photocathode. It shows that gradient-doping NEA GaN photocathode can obtain higher electron escape probability. And barrier I has an evident influence on escape probability while barrier II has limited influence. Photocurrents of two GaN photocathodes are measured with a multi-information-test system. Experimental results show that gradient-doping GaN photocathode has higher escape probability. Obvious effect on escape probability can be found by barrier I from Cs-activation while barrier II from Cs/O-joint-activation has little impact.

关 键 词：表面势垒 梯度掺杂 NEA GAN光电阴极 电子逸出几率 

分 类 号：O462.3[理学—电子物理学]