Crystalline structure, photoluminescence and optical absorption of ß - Ga2S3 crystals

Abstract

Crystalline structure, photoluminescence and optical absorption of Ga2S3 in form of monocrystalline layers at 78K and 293K were investigated. A indirect optical bandgap of 2,94 eV and 3,078 eV was found for monocrystalline samples, and of 3,149 eV and 3,393 eV for direct optical band gap, at 293K and 78K, respectively. The photoluminescence spectrum of monocrystalline layers at 78K consists of three main bands peaked at 2,04 eV, 1,84 eV and 1,66 eV. Structural native defects create deep recombination and electron capture levels within the Ga2S3 band gap.