Structure of GaAs-Ga1−xAlxAs superlattices grown by metal-organic chemical vapour deposition

Abstract

A computer-controlled metal-organic chemical vapour deposition system employing a fast-switching gas manifold has been used to prepare GaAs-Ga1−xAlxAs superlattice structures. A combination of cross-sectional transmission electron microscopy and Auger and secondary ion mass spectrometry sputter profiling have allowed accurate measurements to be made of layer thickness and GaAs-Ga1−xAlxAs interface widths. Layers as thin as 15 Å have been observed and interface widths less than 20 Å measured.