Impact of residual gas on the optoelectronic properties of Cs-sensitized In0.53Ga0.47As (001) surface

Qianglong Fang; Yang Shen; Shuqin Zhang; Xiaodong Yang; Lingze Duan; Liang Chen; Shiqing Xu; Mingxia Gao; Hongge Pan

doi:10.1016/j.jcis.2021.03.043

Impact of residual gas on the optoelectronic properties of Cs-sensitized In_0.53Ga_0.47As (001) surface

J Colloid Interface Sci. 2021 Jul 15:594:47-53. doi: 10.1016/j.jcis.2021.03.043. Epub 2021 Mar 15.

Authors

Qianglong Fang¹, Yang Shen², Shuqin Zhang¹, Xiaodong Yang³, Lingze Duan⁴, Liang Chen⁵, Shiqing Xu¹, Mingxia Gao⁶, Hongge Pan⁶

Affiliations

¹ Institute of Optoelectronics Technology, China Jiliang University, Hangzhou 310018, China.
² Institute of Optoelectronics Technology, China Jiliang University, Hangzhou 310018, China; School of Materials Science and Engineering, Zhejiang University, Zhejiang 310027, China; Hengdian Group Tospo Lighting Co., Ltd., Dongyang 310007, China. Electronic address: yshen1016@foxmail.com.
³ Key Laboratory of Ecophysics and Department of Physics, Shihezi University, Xinjiang 832003, China. Electronic address: yxd1209@shzu.edu.cn.
⁴ Department of Physics, The University of Alabama in Huntsville, Huntsville, AL 35899, USA.
⁵ Institute of Optoelectronics Technology, China Jiliang University, Hangzhou 310018, China. Electronic address: lchen@cjlu.edu.cn.
⁶ School of Materials Science and Engineering, Zhejiang University, Zhejiang 310027, China.

PMID: 33756367
DOI: 10.1016/j.jcis.2021.03.043

Abstract

Near-infrared In_xGa_1-_xAs photocathode with better optoelectronic properties is a good candidate for low-light-level (LLL) night-vision system. However, the residual gases in the ultra-high vacuum (UHV) system inevitably affects the stability and photo-emission performance of LLL photoelectric devices such as their quantum efficiency and life-time. In this study, the first-principles calculations were used to investigate the adsorption effect of five different residual gas species, including H₂, CH₄, CO, H₂O and CO₂ on Cs-sensitized In_0.53Ga_0.47As (001) β₂ (2 × 4) surface. The study results indicate that CO₂ gas molecule is the most easily attached to the Cs-sensitized surface. The adsorption of residual gases leads to the formation of a new dipole pointing from inner Cs atoms to gas molecules. It makes the charge center of the adsorbates escape from the surface, which weakens the interaction between the inner Cs atoms and the clean surface. This results in the increase of the surface work function and degradation of the performance of photoelectric devices. Also, the adsorption of residual gas molecules influences the absorption and reflection coefficients of Cs-sensitized In_0.53Ga_0.47As (001) β₂ (2 × 4) surface.

Keywords: Dipole moments; First-principles calculation; In(0.53)Ga(0.47)As surface; Optical properties; Residual gas.