Origin of the deep center photoluminescence in CuGaSe2 and CuInS2 crystals

Research was conducted to systematically examine the deep photoluminescence bands in CuGaSe2 and CuInS2 single crystals. The band was shown to have a similar doublet structure with the two D1D2 subbands separated by about 100meV in both of the as-grown materials. Results show that the defects constituting the D1 and D2 band recombination centers are chemically identical but structurally slightly different.