Transmission electron microscopy has been used to characterize the microstructure of heteroepitaxial CdTe (111) layers grown by molecular beam epitaxy directly on nominal and misoriented Si(001) substrates. High-resolution electron micrographs showing atomic-scale details of the CdTe (111)/Si(001) interface have been recorded. Layer quality depended on the substrate tilt parameters, including the offcut orientation angle θ, and the azimuthal angle φ relative to . Small φ values (4°and 10°) gave high densities of stacking fault twins throughout the epilayer whereas larger misorientation angles led to a rapid falloff away from the substrate. Under optimized growth conditions, the occurrence of twins effectively dropped to zero within a distance of less than 2.5 μm from the substrate surface.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)