Characterization by photoluminescence of CuGaxIn1-xSe2 thin films prepared by laser deposition

The photoluminescence (PL) spectra of CuInSe₂, CuGaSe₂ and CuGa_xIn_1-xSe₂ thin films were measured in the temperature range 4.2–300 K. The PL spectra of CuInSe₂ are contained many emission bands at 4.2 K in region 0.80–1.05 eV including free-exciton recombination luminescence peaks at 1.041 eV and 1.045 eV. The PL spectra of CuGaSe₂ and CuGa_xIn_1-xSe₂ films also contained many defect-related intense bands. The possible nature of luminescence centers and radiative recombination mechanisms are discussed.