中国物理B ›› 2011, Vol. 20 ›› Issue (11): 118501-118501.doi: 10.1088/1674-1056/20/11/118501

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Improvement of photoemission performance of a gradient-doping transmission-mode GaAs photocathode

张益军, 牛军, 赵静, 熊雅娟, 任玲, 常本康, 钱芸生   

  1. Institute of Electronic Engineering and Optoelectronic Technology, Nanjing University of Science and Technology, Nanjing 210094, China
  • 收稿日期:2011-04-12 修回日期:2011-08-22 出版日期:2011-11-15 发布日期:2011-11-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 60801036 and 61067001), the Key Science and Technology Project of Henan Province of China (Grant No. 112102210202), and the Research and Innovation Plan for Graduate Students of Jiangsu Higher Education Institutions of China (Grant No. CX09B 096Z).

Improvement of photoemission performance of a gradient-doping transmission-mode GaAs photocathode

Zhang Yi-Jun(张益军), Niu Jun(牛军), Zhao Jing(赵静), Xiong Ya-Juan(熊雅娟),Ren Ling(任玲), Chang Ben-Kang(常本康)†, and Qian Yun-Sheng(钱芸生)   

  1. Institute of Electronic Engineering and Optoelectronic Technology, Nanjing University of Science and Technology, Nanjing 210094, China
  • Received:2011-04-12 Revised:2011-08-22 Online:2011-11-15 Published:2011-11-15
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 60801036 and 61067001), the Key Science and Technology Project of Henan Province of China (Grant No. 112102210202), and the Research and Innovation Plan for Graduate Students of Jiangsu Higher Education Institutions of China (Grant No. CX09B 096Z).

PDF (PC)

697

赞

摘要： Two types of transmission-mode GaAs photocathodes grown by molecular beam epitaxy are compared in terms of activation process and spectral response, one has a gradient-doping structure and the other has a uniform-doping structure. The experimental results show that the gradient-doping photocathode can obtain a higher photoemission capability than the uniform-doping one. As a result of the downward graded band-bending structure, the cathode performance parameters, such as the electron average diffusion length and the surface electron escape probability obtained by fitting quantum yield curves, are greater for the gradient-doping photocathode. The electron diffusion length is within a range of from 2.0 to 5.4 μm for doping concentration varying from 1019 to 1018 cm-3 and the electron average diffusion length of the gradient-doping photocathode achieves 3.2 μm.

Abstract: Two types of transmission-mode GaAs photocathodes grown by molecular beam epitaxy are compared in terms of activation process and spectral response, one has a gradient-doping structure and the other has a uniform-doping structure. The experimental results show that the gradient-doping photocathode can obtain a higher photoemission capability than the uniform-doping one. As a result of the downward graded band-bending structure, the cathode performance parameters, such as the electron average diffusion length and the surface electron escape probability obtained by fitting quantum yield curves, are greater for the gradient-doping photocathode. The electron diffusion length is within a range of from 2.0 to 5.4 μm for doping concentration varying from 1019 to 1018 cm-3 and the electron average diffusion length of the gradient-doping photocathode achieves 3.2 μm.

Key words: transmission-mode photocathode, gradient-doping, Cs-O activation, quantum yield

中图分类号:  (Photomultipliers; phototubes and photocathodes)

  • 85.60.Ha
73.61.Ey (III-V semiconductors) 73.20.At (Surface states, band structure, electron density of states) 79.60.-i (Photoemission and photoelectron spectra)