Studies by cross-sectional transmission electron microscope of InAs grown by molecular beam epitaxy on GaAs substrates

We have used the cross-sectional transmission electron microscope to study InAs grown by molecular beam epitaxy. For the InAs films directly grown on GaAs, the dislocation density at the InAs-GaAs interface is several orders of magnitude higher than that in the bulk films. Those grown by the step grading technique show strong interactions among dislocations at the interfaces, and a much reduced dislocation density in the thin InAs layers.