Investigation of Material Structure and Optical Property of Transmission-Mode GaN Photocathode by Ultraviolet Transmission Spectral
DU Xiao-qing，TIAN Jian，ZHOU Qiang-fu
Key Laboratory of Optoelectronic Technology and Systems of Ministry of Education, College of Optoelectronic Engineering, Chongqing University, Chongqing 400044，China
Abstract：GaN UV photocathode has become a high-performance vacuum ultraviolet detectors in recent years. As the photocathode practical application mode, transmission-type multilayer structure and its optical property have important influences on photocathode photoemission performance. Ultraviolet transmission spectra of transmission-mode GaN photocathode were measured. The optical transmission model of transmission-mode GaN photocathode was built, and based on the model the functional relations of thin film thickness and optical adsorption coefficient with transmission spectral were deduced. The error of calculated GaN epitaxial thickness with respect to actual value is very small, and calculated adsorption coefficients are consistent with reported data. It was shown that material structure and optical property of transmission-mode GaN photocathode can be evaluated accurately by this ultraviolet transmission spectral method.
Key words：Ultraviolet transmission spectral;Transmission-mode GaN photocathode;Thin film thickness;Optical adsorption coefficient
杜晓晴，田 健，周强富. 利用紫外透射光谱研究透射式GaN光电阴极的材料结构及光学特性 [J]. 光谱学与光谱分析, 2011, 31(06): 1606-1610.
DU Xiao-qing，TIAN Jian，ZHOU Qiang-fu. Investigation of Material Structure and Optical Property of Transmission-Mode GaN Photocathode by Ultraviolet Transmission Spectral . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2011, 31(06): 1606-1610.
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