TUNABLE GENERATION OF NANOMETER-SCALE CORRUGATIONS ON HIGH-INDEX III-V SEMICONDUCTOR SURFACES

We have investigated by means of in situ reflection high-energy electron diffraction the surface topography of various III(A)III(B)-V and III-V(A)V(B) layers grown by solid-source molecular-beam epitaxy on (311) InP and GaAs substrates. In a wide temperature range, III(A)III(B)-V (311) surfaces are corrugated on a nanometer scale in a way similar to that previously reported for (311) GaAs surfaces [R. Notzel et al., Phys. Rev. Lett. 67, 3812 (1991)]. The geometry of the corrugations can be tuned in a well defined manner by adjusting the overlayer strain. The higher the strain is, the lower the lateral periodicity and the step height are. In addition, the surface of relaxed layers exhibits the structure of the underlying substrate. Finally, on (311)-oriented substrates the relaxation of overlayer strain at least up to 4% occurs without transition toward a three-dimensional agglomerated morphology. This indicates that the surface structure modifies the relaxation paths and mechanisms. On the other hand, the III-V(A)V(B) (311) surfaces are not corrugated. These results are interpreted in terms of the interplay between surface free energy, strain energy, and local-strain fields. We demonstrate that the overlayer strain is the key parameter to control the surface topography. Our work thus provides the means to directly select the interface morphology of semiconductor heterostructures.