Wafer-scale heterogeneous integration of self-powered lead-free metal halide UV photodetectors with ultrahigh stability and homogeneity

Abstract

Large-scale growth and heterogeneous integration with existing semiconductors are the main obstacles to the application of metal halide perovskites in optoelectronics. Herein, a universal vacuum evaporation strategy is presented to prepare copper halide films with wafer-scale spatial homogeneity. Benefiting from the electric field manipulation method, the built-in electric fields are optimized and further boost the self-powered UV photodetecting performances of common wide-bandgap semiconductors by more than three orders of magnitude. Furthermore, with effective modulation of the interfacial charge dynamics, the as-fabricated GaN-substrate heterojunction photodetector demonstrates an ultrahigh on/off ratio exceeding 107, an impressive responsivity of up to 256 mA W–1, and a remarkable detectivity of 2.16 × 1013 Jones at 350 nm, 0 V bias. Additionally, the device exhibits an ultrafast response speed (tr/td = 716 ns/1.30 ms), an ultra-narrow photoresponse spectrum with an FWHM of 18 nm and outstanding continuous operational stability as well as long-term stability. Subsequently, a 372-pixel light-powered imaging sensor array with the coefficient of variation of photocurrents reducing to 5.20% is constructed, which demonstrates exceptional electrical homogeneity, operational reliability, and UV imaging capability. This strategy provides an efficient way for large-scale integration of metal halide perovskites with commercial semiconductors for miniature optoelectronic devices.