A study of spectral response for reflection-mode GaN photocathodes in UVA band

Autor: Hao Guang-Hui, Chen Xin-Long, Chang Ben-Kang, Jin Muchun, Zhao Jing, Wang Xiao-Hui, Xu Yuan
Rok vydání: 2013
Předmět:
Zdroj: Acta Physica Sinica. 62:097901
ISSN: 1000-3290
DOI: 10.7498/aps.62.097901
Popis: In order to understand the spectral response characteristic of the NEA GaN photocathodes at UVA band, three samples grown by MOCVD with different emission layer thickness and doping concentration were activated in the ultra-high vacuum system, and their spectral response were tested online. We fit the experimental quantum efficiency with illumination wavelength between 0.25—0.35 μ by the use of reflection-mode GaN photocathode quantum efficiency formula and the least square approximation method. The back-interface compound rate and the slope of fitting line L are gained and the reflection-mode GaN photocathodes quantum efficiency is simulated with incident light wavelength at 0.35 μ. The results show that the back-interface compound rate and the slope of the fitting line L can reflect GaN photocathode response performance. When the back-interface compound rate of GaN photocathode is less than 105 cm/s and the thickness of the emission layer is set between 0.174—0.212 μ, the photocathode has optimal spectral response performance.
Databáze: OpenAIRE