High-performance CsPbBr3-silicon heterojunction photodetectors fabricated by chemical vapor deposition

Abstract Inorganic perovskite cesium lead halide (CsPbBr 3 ) has attracted extensive research attention due to its excellent photoelectric properties and long-term stability to water, oxygen, light and heat. In this work, high crystallinity CsPbBr 3 microcrystals with different morphologies and grain sizes were synthesized by one-step chemical vapor deposition (CVD) on silicon (Si) wafers and silicon nanowires (SiNWs), respectively. Characterization results show that the CsPbBr 3 microcrystals grown on SiNWs (CsPbBr 3 -SiNWs) display more compact and uniform morphologies than those grown on Si wafer (CsPbBr 3 -Si). Moreover, CsPbBr 3 -SiNWs exhibits higher detectivity and larger on/off ratio than CsPbBr 3 -Si, which are 5.1 × 10 12 Jones over 3.4 × 10 12 Jones, and 51.3 over 14.7, respectively. Furthermore, CsPbBr 3 -SiNWs shows a faster photo response with a rise/fall time of 0.22 s/0.28 s than 0.26 s/0.32 s in CsPbBr 3 -Si. In addition, the CsPbBr 3 -SiNWs photodetector maintained 90% of its original photocurrent after 60 days of exposure to air, showing excellent stability. These results strongly suggest a promising fabrication approach for constructing perovskite-based heterojunction optoelectronic devices with high performance and excellent stability.