Deep defect related photoluminescence in heavily doped CuGaTe2crystals

✍ Scribed by Jagomägi, Andri ;Krustok, Jüri ;Grossberg, Maarja ;Danilson, Mati ;Raudoja, Jaan

• Book ID: 105363349
• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 365 KB
• Volume: 203
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200521118

✦ Synopsis

Abstract

CuGaTe~2~ samples very often exhibit optical and electrical properties of heavily doped semiconductors. This paper investigates the low temperature photoluminescence properties of polycrystalline CuGaTe~2~ samples. The photoluminescence spectra of “heavily doped” semiconductors are usually characterized by the broadening of the photoluminescence bands that is caused by the fluctuations of the forbidden band edges. The deep photoluminescence region observed (0.8–1.3 eV) consists of two peaks. One of them is located at 0.955 eV and has been reported before. Another, totally new band was discovered at 1.14 eV. The low‐temperature j‐shift of both bands was detected. Also, rather significant blue shift with the increasing temperature was noticed. It is proposed that both bands consist of two recombination channels. At low temperatures tail‐to‐impurity recombination dominates. As the temperature increases, the tail‐to‐impurity recombination transforms into band‐to‐impurity recombination. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)