Molecular-beam epitaxial GaAs/AlAs superlattices in the (311) orientation

Abstract

We observed flat, smooth heterointerfaces in GaAs/AlAs superlattices grown on GaAs (311)A by molecular-beam epitaxy. In our investigation of GaAs/AlAs superlattice structures along both the [011] and [233] directions by cross-section transmission-electron microscopy, we found that the heterointerfaces formed in the (311)A orientation are sharp and smooth. This indicates that the GaAs (311)A surface is stable for epitaxial growth. Thus, it is clear that the recently reported occurrence of interface corrugation in the GaAs/AlAs superlattice grown on GaAs (311)A substrates, viewed along the [233] direction, is not intrinsic to the (311) surfaces. © 1994 The American Physical Society.