High-quality InSe thin films and PbSe/InSe/PbSe barrier detector by thermally evaporated deposition

Indium Selenide (InSe) exhibits outstanding photoelectronic properties, making it a subject of great interest in optoelectronic devices. A challenge in high-quality InSe thin films arises from the multivalency of indium. Herein, high-purity InSe thin films were deposited by using vacuum thermal evaporation technology, and the impact of growth and annealing temperature on the thin film’s quality was investigated. The content of In 2 Se 3 decreases with increasing the substrate temperatures, and monoclinic phase InSe with high purity is obtained at 350 °C. No significant change was observed in both peak intensity and full-width at half-maximum (FWHM) of InSe thin films after annealing. Meanwhile, a PbSe/InSe/PbSe pBp barrier infrared detector based on PbSe absorber layer was designed and manufactured by thermal evaporation technology, and exhibits a peak detectivity of 8.6 × 10 7 cm Hz 1/2 W −1 at room temperature. These results indicate that high-quality InSe thin films could be adopted to construct PbSe/InSe heterojunction detector with high replicability and stability, making them a potential value in uncooled middle-wavelength infrared detection.