Amorphous effect on the advancing of structural-phase transition in γ-In2Se3 polycrystalline layers

We demonstrate a III-VI chalcogenide, polycrystalline γ-In2Se3, which simultaneously possesses the capabilities of thickness-dependent optical gaps and wide-energy-range absorption existed in the polycrystalline layers of γ-In₂Se₃. The amorphous effect of medium-range order (MRO) renders a structural-phase transition of γ → α occurred inside the γ-In₂Se₃ layer with a heat treatment of about 700 °C. Photo V-I measurements of different-thickness γ-In₂Se₃ layers propose a wide-energy-range photoelectric conversion unit ranging from visible to UV may be achieved by stacking the γ-In₂Se₃ layers in a staircase form containing dissimilar optical gaps. The results are demonstrated here in.