Raman scattering characterization of strain in gaas heteroepitaxial films grown on sapphire and silicon-on-sapphire substrates

Contributors:   T.P. Humphreys, J.B. Posthill, K. Das, C.A. Sukow, R.J. Nemanich, N.R. Parikh, and A. Majeed

ABSTRACT

We report results pertaining to the measurement of strain by Raman spectroscopy in GaAs epitaxial films grown by molecular beam epitaxy on sapphire and silicon-on-sapphire substrates. Comparative studies indicate that the GaAs layers deposited directly on sapphire substrates show no measurable strain, and only a small residual tensile strain is observed in the films grown on silicon-on-sapphire substrates. The magnitude of the strain in the GaAs/silicon-on-sapphire heterostructures is reduced by over a factor of 4.5 as compared to that observed in the GaAs films deposited directly on single-crystal silicon (100) substrates under the same growth conditions.

Publisher: Japanese Journal of Applied Physics,   Volume: 28,   Published: 1989-01 ||   Read more...