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NEA GaN和GaAs光电阴极的比较

Comparison of NEA GaN and GaAs Photocathodes

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摘要

针对GaN 基光电阴极激活过程中Cs-O 交替存在的光电流的增幅问题,本文主要比较了GaN和GaAs 材料性质、表面结构以及激活过程中光电阴极的光电流。发现GaN 的熔点高于GaAs,在制备GaN基光电阴极时则需要更高的热清洗温度;如果用双偶极子模型描述GaN(1000)和GaAs(100)表面的光电发射机理,GaN(1000)表面Cs 原子与O 原子形成第二偶极矩O-Cs,几乎“平躺”在表面,对光电发射贡献不大;GaAs(100)表面Cs 原子与O 原子形成第二偶极矩O-Cs 几乎“垂直”于表面,降低了表面功函数,对光电发射贡献很大;Cs-O 激活过程中,对于GaAs 光电阴极,Cs、O交替过程形成的光电流与单纯Cs 激活时的光电流相比,有几倍甚至上百倍的增长;GaN 只提高了20%左右。通过第一性原理计算,与现在的GaN 基(1000)面相比,GaN 基的(1120)和(1010)面是极具潜力的光电发射面;预计闪锌矿GaN 基(100)面会取得更好的结果。

Abstract

In view of the increase in photocurrent in the alternation of Cs-O in the activation process of GaN-based photocathode, in this paper, the properties of GaN and GaAs materials, the surface structure, and the photocurrent of the photocathode during the activation process are compared. It is found that the melting point of GaN is higher than that of GaAs, and a higher thermal cleaning temperature is necessary in the preparation of GaN-based photocathode. Using the double dipole model to describe the photoelectric emission mechanism of the GaN(1000) and GaAs(100) surface, the GaN(1000) surface Cs atoms and O atoms form the second dipole moment of O-Cs that is almost flat on the surface and contribute little to the photoelectric emission; the GaAs(100) surface Cs atoms and O atoms form the second dipole moment of O-Cs that is almost vertical to the surface, reducing the surface work function of the photoelectric emission contribution. In the Cs-O activation, the photocurrent formed by the alternating process of Cs and O for the GaAs photocathode could be several times even more than 100 times higher than that of pure Cs activation, whereas the GaN photocathode only increases by ~20%. By first principle calculations, compared to the GaN(1000) surface ratio, GaN base(1120) and (1010) are the photoelectric emission potential surface; and the sphalerite GaN base(100) surface is expected to achieve better results.

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中图分类号:TN14

所属栏目:综述与评论

基金项目:国家自然科学基金重大研究计划(91433108)。

收稿日期:2017-11-17

修改稿日期:2017-12-05

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常本康:南京理工大学 电子工程与光电技术学院,江苏 南京 210094

备注:常本康(1950-),博士,教授,博导,主要研究方向为微光夜视和多光谱图像融合技术。

【1】常本康.GaAs基光电阴极[M].北京:科学出版社,2017.
CHANG Benkang. GaAs Based Photocathode[M]. Beijing: Science Press, 2017.

【2】Aebi V W, Costello K A, Aruni P W, et al. EBAPS: next generation, low power, digital night vision[C]//The OPTRO 2005 International Symposium, Paris: 2005.

【3】郝广辉.AlGaN光电阴极研制及性能评估[D].南京:南京理工大学,2015.
HAO Guanghui. Development and Performance Evaluation of AlGaN Photocathode[D]. Nanjing: Nanjing University of Science & Technology, 2015.

【4】王晓晖.纤锌矿结构GaN(0001)面光电发射性能研究[D].南京:南京理工大学,2013.
WANG Xiaohui. Study on Photoemission Properties of GaN(0001) Surface of Wurtzite[D]. Nanjing: Nanjing University of Science & Technology, 2013.

【5】CHANG Benkang, LIU Wenli, FU Rongguo et al. Spectral response and surface layer thickness of GaAs: Cs-O negative electron affinity photocathode[C]//Proc. SPIE, 2001, 4580: 632-641.

【6】LIU Wenli, WANG Hui, CHANG Benkang, et al. A study of the NEA photocathode activation technique on [GaAs(Zn):Cs]: O-Cs model [C]//SPIE, 2006, 6352: 63523A.

【7】ZHANG Yijun, ZOU Jijun, WANH Xiaohui, et al. Comparison of the photoemission behaviour between negative electron affinity GaAs and GaN photocathodes[J]. Chinese Physics B, 2011, 20(4): 048501.

【8】YANG Mingzhu, CHANG Benkang, HAO Guanghui, et al. Electronic structure and optical properties of nonpolar Ga0.75Al0.25N surfaces[J]. OPTIK, 2014, 125: 6260-6265.

【9】杨明珠.Ga1-xAlxN光电阴极的光电性质与铯氧激活机理研究[D].南京:南京理工大学,2016.
YANG Mingzhu. Study on the photoelectric properties of Ga1-xAlxN photocathodes and the mechanism of activation of cesium and oxygen[D]. Nanjing: Nanjing University of Science & Technology, 2016.

引用该论文

CHANG Benkang. Comparison of NEA GaN and GaAs Photocathodes[J]. Infrared Technology, 2017, 39(12): 1073-1077

常本康. NEA GaN和GaAs光电阴极的比较[J]. 红外技术, 2017, 39(12): 1073-1077

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