中国物理B ›› 2013, Vol. 22 ›› Issue (2): 27901-027901.doi: 10.1088/1674-1056/22/2/027901

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Influence of wet chemical cleaning on quantum efficiency of GaN photocathode

王晓晖, 高频, 王洪刚, 李飙, 常本康   

  1. Institute of Electronic Engineering and Optoelectronic Technology, Nanjing University of Science and Technology, Nanjing 210094, China
  • 收稿日期:2012-04-17 修回日期:2012-08-24 出版日期:2013-01-01 发布日期:2013-01-01
  • 基金资助:
    Projects supported by the National Natural Science Foundation of China (Grant No. 60871012); the National Key Laboratory of Science and Technology Foundation on Low Light Level Night Vision (Grant No. J20110104); and the Research and Innovation Plan for Graduate Students of Jiangsu Higher Education Institutions (Grant No. CXZZ11_0238).

Influence of wet chemical cleaning on quantum efficiency of GaN photocathode

Wang Xiao-Hui (王晓晖), Gao Pin (高频), Wang Hong-Gang (王洪刚), Li Biao (李飙), Chang Ben-Kang (常本康)   

  1. Institute of Electronic Engineering and Optoelectronic Technology, Nanjing University of Science and Technology, Nanjing 210094, China
  • Received:2012-04-17 Revised:2012-08-24 Online:2013-01-01 Published:2013-01-01
  • Contact: Chang Ben-Kang E-mail:bkchang@njust.mail.edu.cn
  • Supported by:
    Projects supported by the National Natural Science Foundation of China (Grant No. 60871012); the National Key Laboratory of Science and Technology Foundation on Low Light Level Night Vision (Grant No. J20110104); and the Research and Innovation Plan for Graduate Students of Jiangsu Higher Education Institutions (Grant No. CXZZ11_0238).

摘要: GaN samples 1-3 are cleaned by a 2:2:1 solution of sulfuric acid (98%) to hydrogen peroxide (30%) to de-ionized water; hydrochloric acid (37%); or a 4:1 solution of sulfuric acid (98%) to hydrogen peroxide (30%). The samples are activated by Cs/O after the same annealing process. X-ray photoelectron spectroscopy after the different ways of wet chemical cleaning shows: sample 1 has the largest proportion of Ga, N, and O among the three samples, while its C content is the lowest. After activation the quantum efficiency curves show sample 1 has the best photocathode performance. We think the wet chemical cleaning method is a process which will mainly remove C contamination.

关键词: GaN photocathode, X-ray photoelectron spectroscopy, wet chemical cleaning, quantum efficiency

Abstract: GaN samples 1-3 are cleaned by a 2:2:1 solution of sulfuric acid (98%) to hydrogen peroxide (30%) to de-ionized water; hydrochloric acid (37%); or a 4:1 solution of sulfuric acid (98%) to hydrogen peroxide (30%). The samples are activated by Cs/O after the same annealing process. X-ray photoelectron spectroscopy after the different ways of wet chemical cleaning shows: sample 1 has the largest proportion of Ga, N, and O among the three samples, while its C content is the lowest. After activation the quantum efficiency curves show sample 1 has the best photocathode performance. We think the wet chemical cleaning method is a process which will mainly remove C contamination.

Key words: GaN photocathode, X-ray photoelectron spectroscopy, wet chemical cleaning, quantum efficiency

中图分类号:  (Photoemission and photoelectron spectra)

  • 79.60.-i
72.80.-r (Conductivity of specific materials) 73.20.-r (Electron states at surfaces and interfaces) 73.61.-r (Electrical properties of specific thin films)