STUDY OF THE EPITAXIAL-GROWTH OF GAAS(110) FILMS BY MOLECULAR-BEAM EPITAXY

The epitaxial growth of GaAs(110) films by molecular beam epitaxy has been investigated in situ by reflection high-energy electron diffracti on (RHEED). In comparison to the GaAs(001) surface it is necessary to grow GaAs(110) at much lower temperatures to obtain films with good su rface morphology. The period of the RHEED oscillations shows a transit ion from monolayer to bilayer growth as the temperature is reduced and growth occurs under more arsenic rich conditions. At high temperature s (>500-degrees-C), oscillations show a continuous increase in period to a value several times that expected for monolayer growth. This beha vior is explained in terms of a decrease in the sticking coefficient o f AS2 with increasing temperature which leads to Ga-rich growth and a growth rate which is limited by the incident AS2 flux.