Optical parameters in SnO2 nanocrystalline textured films grown on p-InSb (111) substrates

Spectroscopic ellipsometry and photoluminescence (PL) measurements on SnO2 nanocrystalline textured films grown on p-InSb (111) substrates by using radio-frequency magnetron sputtering at low temperature were carried out to investigate the dependence of the optical parameters on the SnO2 thin film thickness. As the SnO2 film thickness increases, while the energy gap of the SnO2 film decreases, its refractive index increases. The PL spectra show that the broad peaks corresponding to the donor-acceptor pair transitions are dominant and that the peak positions change with the SnO2 film thickness. These results can help improve understanding for the application of SnO2 nanocrystalline thin films grown on p-InSb (111) substrates in potential optoelectronic devices based on InSb substrates. (C) 2002 Elsevier Science Ltd. All rights reserved.