The optimal thickness of transmission-mode GaN photocathode
(0) 150 nm thick GaN photocathode with Mg doping concentration of 1.6×1017 cm-3 is activated by Cs/O in ultrahigh vacuum chamber,and quantum efficiency (QE) curve of negative electron affinity transmission-mode (t-mode) GaN photocathode is obtained.The maximum QE reach 13.0% at 290 nm.According to the t-mode QE equation solved from the diffusion equation,the QE curve is fitted.From the fitting results,the electron escape probability is 0.32,the back-interface recombination velocity is 5×104 cm·s-1,and the electron diffusion length is 116 nm.Based on these parameters,the influence of GaN thickness on t-mode QE is simulated.The simulation shows,the optimal thickness of GaN is 90 nm,which is higher than the 150 nm GaN.
Gallium Nitride transmission-mode quantum efficiency optimal thickness
王晓晖 石峰 郭晖 胡仓陆 程宏昌 常本康 任玲 杜玉杰 张俊举
国内会议
南京
英文
1-6
2012-06-08（万方平台首次上网日期，不代表论文的发表时间）