Growth modes of ZnSe on GaAs

Growth modes of coherently strained ZnSe on GaAs are investigated as a function of the surface preparation and temperature. We find that the flattest and most uniform layers are grown at low temperatures, ∼300 °C, on surfaces exposed to high-temperature Se treatment. Nucleation rate depends on the surface coverage of Ga2Se3. High-temperature exposure of Ga-rich, (001)-oriented, GaAs to Se reduces the thickness required for the transition to a two-dimensional growth mode. The surface roughness increases with temperature as a result of three-dimensional island growth.