CuInSe2

CuInSe₂ is a ternary chalcopyrite semiconductor compound composed of copper, indium, and selenium, belonging to the I-III-VI₂ family of direct bandgap semiconductors. It is primarily employed as an absorber layer in thin-film photovoltaic (PV) devices, particularly in CIGS (copper indium gallium selenide) solar cells, where it enables efficient light-to-electricity conversion with lower material consumption than silicon-based alternatives. The material is notable for its high optical absorption coefficient, tunable bandgap, and established scalability to large-area manufacturing, making it attractive for space applications, building-integrated photovoltaics, and flexible solar technologies where weight and efficiency density are critical.