Title :
The effect of Se content on defect levels in CuInSe2 single crystals detected by photoacoustic spectrometry
Author :
Zegadi, A. ; Yakushev, M.V. ; Ahmed, E. ; Slifkin, M.A. ; Hill, A.E. ; Tomlinson, R.D.
Author_Institution :
Dept. of Electron. & Electr. Eng., Salford Univ., UK
Abstract :
The objective of this paper is to investigate the impact of changes in the selenium content of thin-film solar cell CuInSe2 single crystals on their optical properties in the subgap region of the infrared spectrum. A high resolution near-infrared photoacoustic spectrometer of the gas-microphone type is used for room temperature analysis of nonradiative defect states in as-grown n and p-type CIS crystals. Samples with an excess and a deficiency of Se (5% off the stoichiometric composition), were grown from the melt by the vertical Bridgman technique. The absorption coefficient has been derived from photoacoustic spectra in order to establish activation energies for several defect-related energy levels
Keywords :
copper compounds; crystal growth from melt; defect states; indium compounds; photoacoustic spectra; photoacoustic spectroscopy; semiconductor device testing; semiconductor growth; solar cells; ternary semiconductors; CuInSe2; absorption coefficient; activation energies; defect levels; defect-related energy levels; gas-microphone type; melt growth; near-infrared photoacoustic spectrometer; nonradiative defect states; optical properties; photoacoustic spectrometry; resolution; room temperature analysis; selenium content; single crystals; solar cell; stoichiometric composition; subgap region; thin-film semiconductor; vertical Bridgman technique; Absorption; Computational Intelligence Society; Crystals; Educational institutions; Energy states; Frequency; Infrared spectra; Optical films; Spectroscopy; Temperature;
Conference_Titel :
Photovoltaic Energy Conversion, 1994., Conference Record of the Twenty Fourth. IEEE Photovoltaic Specialists Conference - 1994, 1994 IEEE First World Conference on
Conference_Location :
Waikoloa, HI
Print_ISBN :
0-7803-1460-3
DOI :
10.1109/WCPEC.1994.519849
