Low temperature air-annealing of Cu(InGa)Se 2 single crystals

• Published in: Thin solid films Vol. 511; pp. 135 - 139
• Main Authors: Yakushev, M.V., Jack, A., Pettigrew, I., Feofanov, Y., Mudryi, A.V., Krustok, J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 26-07-2006
• Subjects: CuInGaSe 2; Oxygen; Photoluminescence; CuInGaSe 2; Oxygen; Photoluminescence
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2005.11.089

CuInSe
2 and CuIn
0.95Ga
0.05Se
2 single crystals, grown by vertical Bridgman, were annealed in air at temperatures from 100 to 160 °C. Both CuInSe
2 and CuIn
0.95Ga
0.05Se
2 samples were studied using photoluminescence (PL). The CuInSe
2 samples were also studied using Rutherford Backscattering Channeling (RBS/C) and nuclear reaction analysis (NRA). Before annealing the samples showed low dechanneling parameters suggesting high quality lattice structure. The PL spectra of both CuInSe
2 and CuIn
0.95Ga
0.05Se
2 revealed bands associated with band-tail recombination mechanism. Annealing at 120 °C and higher temperatures considerably modified the RBS/C and PL spectra. NRA indicated a gradual increase in the oxygen content. PL analysis suggested that annealing increases both the mean-square amplitude of potential fluctuations and the level of compensation. Changes in the RBS/C spectra demonstrated that annealing at up to 160 °C does not result in the growth of In
2O
3 surface layer but modifies primarily the Se- and Cu-related RBS/C yield. These modifications are consistent with an increase in the concentration of defect complexes.