High-performance layer-structured Si/GaO/CHNHPbI heterojunction photodetector based on a GaO buffer interlayer.

Organic-inorganic metal halide perovskite-based photodetectors (PDs) have attracted great attention because they exhibit extraordinary optoelectronic performances due to advantages such as a low trap-state density and large absorption coefficient. As a buffer layer, can block electron hole recombination, passivate an Si surface, reduce trap density, and improve the ability of electron tunneling. Here, we demonstrate a trilayer hybrid structure ( / / ) composed of an n-type silicon wafer, interlayer, and thin film. The effect of different layer thicknesses on the characteristics of a PD was studied, which shows that the responsivity first increases and then decreases with an increase in the film thickness; the optimized thickness is 300 nm. Additionally, the optimal responsivity, detectivity, and the rise and decay times are 7.2 , 7.448×10 Jones, and 39 and 1.7 ms, respectively. This device has a better performance because and perovskite have a matched energy level. We believe our work could provide a new way to fabricate high-performance optoelectronic devices.