Greatly improved photoresponse in the MAPbBr<sub>3</sub>/Si heterojunction by introducing an ITO layer and optimizing MAPbBr<sub>3</sub> layer thickness
Siyang Guo, Shuang Qiao, Jihong Liu, Jikui Ma, Shufang Wang
Abstract
In this paper, a CH 3 NH 3 (MA)PbBr 3 /Si heterojunction photodetector (PD) is prepared, and a simple method is proposed to improve the performance by introducing an ITO conductive layer and modulating thickness of the MAPbBr 3 layer. The results indicate that the MAPbBr 3 /Si heterojunction PD exhibits an ultra-broadband photoresponse ranging from 405 to 1064 nm, and excellent performances with the responsivity ( R ) of 0.394 mA/W, detectivity ( D ) of 0.11×10 10 Jones, and response times of ∼2176/∼257 ms. When adding the ITO layer, the R and D are greatly improved to 0.426 A/W and 5.17×10 10 Jones, which gets an increment of 1.08×10 5 % and 4.7×10 3 %, respectively. Meanwhile, the response times are reduced to ∼130/∼125 ms, and a good environmental stability is obtained. Moreover, it is found that the photoresponse is strongly dependent on the thickness of the MAPbBr 3 layer. By modulating the MAPbBr 3 layer thickness from ∼85 to ∼590 nm, the performances are further improved with the best R of ∼0.87 A/W, D of ∼1.92×10 11 Jones, and response times of ∼129/∼130 ms achieved in the ∼215 nm-thick PD.