Feng-Xia Liang, Jing-Jing Jiang, Yao-Zu Zhao, Zhi-Xiang Zhang, Di Wu, Long-Hui Zeng, Yuen Hong Tsang*

 Lin-Bao Luo,* 

Abstract:In this study, MAPbBr₃ single crystal (MSC) p-n perovskite homojunction photodiode and n-p-n phototriode have been successfully fabricated through controlled incorporation of Bi³⁺ ions in solution. Optoelectronic analysis reveals that the photodiode shows typical photovoltaic behavior and best photovoltaic performance can be achieved when the n-type MSC was grown in 0.3% Bi³⁺ feed solution. The as-assembled p-n MSC photovoltaic detector displays obvious sensitivity to 520 nm illumination, with a high responsivity of up to 0.62 A/W and a specific detectivity of 2.16×10¹² Jones, which surpassed many MSC photodetectors previously reported. Further performance optimization could be realized by constructing an n-p-n phototriode using the same growth method. The photocurrent magnification rate of the as-fabricated n-p-n phototriode can reach a maximum value of 2.9×10³. Meanwhile, a higher responsivity of 14.47 A/W, specific detectivity of 4.67×10¹³ Jones and an external quantum efficiency (EQE) of up to 3.46×10³ were achieved under an emitter-collector bias of 8V. These results confirm that the present p-n and n-p-n MSC homojunction are promising device configurations which may find potential application in future optoelectronic devices and systems.