Structural Characteristics and Photoluminescence of Thin Films of Cu(In1–xgax)(Syse1–y)2 Solid Solutions.

The phase composition and structural and optical characteristics of thin films of Cu(In_1–xGa_x)(SySe_1–y)₂ solid solutions with the chalcopyrite structure were investigated. The unit-cell constants according to x-ray diffraction analysis were a ~ 5.720 Å and c ~ 11.52 Å. The elemental compositions were x = Ga/(Ga + In) ~ 0.14 and y = S/(S + Se) ~ 0.11 for Cu(In_1–xGa_x)(S ySe_1–y)₂ thin films. The optical band gap of Cu(In_1–xGa_x)(S ySe_1–y)₂ solid solutions determined from measurements of photoluminescence spectra and luminescence excitation spectra at ~4.2 K was E_g ~ 1.122 eV. The mechanism of radiative recombination of nonequilibrium charge carriers in thin films of Cu(In_1–xGa_x) (S ySe_1–y)₂ solid solutions is discussed. [ABSTRACT FROM AUTHOR]