Influence of defect generation processes in CdIn2S4 single crystals on the photoluminescence and Raman scattering spectra

Abstract

Photoluminescence (PL) and Raman scattering (RS) spectra obtained in CdIn2S4 single crystals in dependence of the applied heat treatment conditions are studied. The possibility is considered to explain the deformation of the integral PL spectrum by a model within which the local levels are due to the intrinsic defects of the ternary semiconductor. The presence of a wide-band background in the RS spectra and the evident deformation of the PL spectra characteristic for sample subjected to a rapid cooling after annealing at temperatures not lower than Tc ≈︁ 300 to 320 °C are interpreted as being the result of a phase transition of the order-disorder type. The latter occurs at T ≈︁ Tc and causes the conversion of the CdIn2S4 crystal structure from a normal spinel (T < Tc) into a partially inverted one (T > Tc ≈︁ 320 °C).