Effect of in situ O+ beam induction on the microstructures and optical properties of polycrystalline lead selenide films

[Display omitted] •Tuning optical properties of PbSe via an in-situ O+ beam method was presented.•Three types of special microstructures were induced by an O+ beam.•The optical bandgap was tuned to be more effective for mid infrared applications.•A structurally well-ordered microstructure with sharp Urbach slope was obtained. Tuning optical properties for narrow band gap semiconductors is attractive and meaningful for infrared optical and optoelectronic devices. Here, we demonstrate the impacts of O+ beam on morphological, structural and optical properties of polycrystalline PbSe thin films using an L9 (33) orthogonal experimental design. Three types of specific surface microstructures were induced by ion beam. Morphological evolutions were revealed to be manipulated by beam configurations. Tunable optical band gap and enhanced absorbance were also induced by ion beam modifications. The structural properties and the Urbach energy as low as ∼2 meV both suggest a well-ordered microstructure of this material with high crystallinity.