Electrochemical synthesis of CuIn(S,Se)2 alloys with graded composition for high efficiency solar cells

This work reports the electrochemical synthesis and characterization of CuIn(S,Se)(2) layers with graded composition from a S-rich surface region toward a Se-rich back region. The process includes the single step electrodeposition of a CuInSe2 precursor followed by a sulfurization step. Cross-sectional Raman microprobe measurements have allowed to characterize the complex graded structure of the layers. These data have been correlated with in-depth Auger electron spectroscopy and x-ray diffraction. Preliminary simulations of solar cells with different kinds of absorbers corroborate the potential of these complex graded layers for the development of low cost high efficiency devices.