Slightly Cu-rich CuGaSe2 films were grown on  oriented GaAs substrates by molecular beam epitaxy. Photoluminescence of the films showed a remarkable emission peaked at 1.71eV at low temperature. It is revealed to be a complex attributable to recombination of free excitons and that of bound excitons. The dissociation energy of free excitons and their localization energy to a center are found to be 16.2meV and 3.3meV, respectively. The band-gap energy, Eg, is estimated to be 1.7310eV at low temperature. It is suggested that the temperature variation of Eg is caused by interaction with phonons of 26meV which corresponds to the mean value of optical phonons.
|Number of pages||6|
|Journal||Denshi Gijutsu Sogo Kenkyusho Iho/Bulletin of the Electrotechnical Laboratory|
|Publication status||Published - 1996 Jan 1|
ASJC Scopus subject areas
- Condensed Matter Physics
- Electrical and Electronic Engineering