Imaging the evolution of lateral composition modulation in strained alloy superlattices.
Scanning tunneling microscopy is used to investigate the morphological evolution of GaAs/InAs short period superlattice structures. The layers of the superlattice, either grown in compression or tension, exhibit an island or trench morphology. With increasing film thickness, the islands or trenches grow in size and develop a characteristic spacing along [110] of approximately 150 A. This is the first experimental evidence to suggest that lateral composition modulation arises from both thickness variations of the layers and compositional nonuniformities within the atomic plane.
Department of Computer Science, Engineering Science, and Physics, The University of Michigan-Flint, Flint, Michigan 48502, USA.
Chris
C
Pearson
C
C
Dorin
J
J
Mirecki Millunchick
B G
BG
Orr