GaAs film deposited on SrTiO3 substrate by molecular beam epitaxy

GaAs films grown on ferroelectric SrTiO3 substrates by molecular beam epita xy are characterized, to the best of our knowledge, for the first time by u sing photoluminescence (PL), scanning electron microscopy and secondary-ion mass spectrometry measurement techniques. The results show that under the current growth conditions the deposited GaAs material first forms 3D island s on the SrTiO3 substrates and then with further increase in deposition thi ckness of GaAs, a GaAs film with a very rough surface is formed. Optical tr ansitions close to GaAs band-gap energy are observed for both the thin and the relatively thick samples. The transition energy of the observed emissio n labeled as F in the PL spectra shows a significant blue shift in comparis on with the energy of the band-gap emissions in bulk GaAs. (C) 2000 Elsevie r Science B.V. All rights reserved.