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

Abstract

Abstract Inorganic perovskite cesium lead halide (CsPbBr3) 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 CsPbBr3 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 CsPbBr3 microcrystals grown on SiNWs (CsPbBr3-SiNWs) display more compact and uniform morphologies than those grown on Si wafer (CsPbBr3-Si). Moreover, CsPbBr3-SiNWs exhibits higher detectivity and larger on/off ratio than CsPbBr3-Si, which are 5.1 × 1012 Jones over 3.4 × 1012 Jones, and 51.3 over 14.7, respectively. Furthermore, CsPbBr3-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 CsPbBr3-Si. In addition, the CsPbBr3-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.