Studies of carrier recombination in solution-processed CuIn(S,Se)2 through photoluminescence spectroscopy

We investigated the effects of the cadmium sulfide (CdS) layer on defect passivation in hydrazine-based CuIn(S,Se)(2) (CISSe) samples through photoluminescence measurements. Significant changes in the emission profile of the CISSe film are observed after a CdS layer is deposited on CISSe. It is likely that Cd diffusion into the CISSe film becomes more severe as a result of the fine grain size of our solution-processed films. Enhanced emission yields and longer carrier lifetimes are, thus, observed in Cd-treated (CdS-coated or Cd-soaked) CISSe films, indicating the action of Cd ions on Cu vacancies sites and a decrease in non-radiative recombination. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4792738]