CuIn(SxSe1-x)2 thin films by sulfurization

Polycrystalline films of the quaternary alloy CuIn(S x Se 1- x ) 2 with a thickness of 1 to 3 µm have been synthesized by sulfurization of InSe/Cu precursors. The films have been characterized with respect to their composition and their optical and their electronic properties. X-ray diffraction measurements of the CuIn(S x Se 1- x ) 2 alloy films showed a shift of their (112) diffraction peaks corresponding to the S/(S+Se) composition ratio between 0.5 and 0.9. The optical transmission measurements revealed that the band gap of the alloy films shifts from 1.24 to 1.48 eV with increase of the composition ratio. All CuIn(S x Se 1- x ) 2 alloy films prepared by this method exhibited p-type conduction which was determined using a thermoprobe. Electrical transport properties were assessed by Hall measurements in the van der Pauw geometry.