Defect recombination suppression and carrier extraction improvement for efficient CsPbBr3/SnO2heterojunction photodetectors

Qianwen Zhang; Lijuan Yao; Bobo Li; Dan Fang; Dengkui Wang; Jinhua Li; Xiaohua Wang; Peigang Han; Mingxia Qiu; Xuan Fang

doi:10.1088/1361-6528/acb713

Defect recombination suppression and carrier extraction improvement for efficient CsPbBr₃/SnO₂heterojunction photodetectors

Nanotechnology. 2023 Mar 20;34(23). doi: 10.1088/1361-6528/acb713.

Authors

Qianwen Zhang¹, Lijuan Yao¹, Bobo Li², Dan Fang¹, Dengkui Wang¹, Jinhua Li¹, Xiaohua Wang¹, Peigang Han², Mingxia Qiu², Xuan Fang^{1

3}

Affiliations

¹ State Key Laboratory of High Power Semiconductor Lasers, School of Physics, Changchun University of Science and Technology, 7089 Wei-Xing Road, Changchun 130022, People's Republic of China.
² College of New Materials and New Energies, Shenzhen Technology University, Shenzhen, Guangdong 518118, People's Republic of China.
³ School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, People's Republic of China.

PMID: 36716478
DOI: 10.1088/1361-6528/acb713

Abstract

Perovskite materials with excellent optical and electronic properties have huge potential in the research field of photodetectors. Constructing heterojunctions and promoting carrier transportation are significant for the development of perovskite-based optoelectronics devices with high performances. Herein, we demonstrated a CsPbBr₃/SnO₂heterojunction photodetector and improved the device performances through post-annealing treatment of SnO₂film. The results indicated that the electrical properties of SnO₂films will make an important impact on carrier extraction, especially for type-II heterojunction. As the electrons transfer layer in CsPbBr₃/SnO₂type-II heterojunction, defects related to oxygen vacancy should be the key factor to affect carrier concentration, induce carriers' limitation and recombination rate. Under proper annealing temperature for SnO₂layer, the recombination rate can decrease to 1.37 × 10²¹cm³s and the spectral responsivity will be highly increased. This work can enhance the understanding on the photoresponse of perovskite photodetectors, and will be helpful for the further optimization and design of optoelectronic devices based on the perovskite heterojunction.

Keywords: carrier transport; inorganic interface; perovskite photodetector; post-treatment.