In-depth resolved Raman scattering analysis of secondary phases in Cu-poor CuInSe2 based thin films

Abstract

Raman scattering analysis of Cu-poor CuInSe2 layers shows the coexistence of the ordered vacancy compound (OVC), CuAu- CuInSe2 and chalcopyrite (CH) CuInSe2 phases as function of the Cu/In content ratio x. In-depth resolved measurements from layers with x≤0.57 show a strong inhibition in the relative intensity of the CH- CuInSe2 mode at the back region. Micro-Raman spectra directly measured at different regions from the layers with 0.66≤x≤0.71 also suggest a higher content of the OVC phase at this back region. These data suggest an enhancement in the formation of OVC at this region in the layers. © 2009 American Institute of Physics.