Transmission electron microscopy was used to study the microstructure of hetero-epitaxial CdTe (111) layers which had been grown, by means of molecular beam epitaxy, directly onto nominal or misoriented Si(001) substrates. High-resolution electron micrographs which revealed atomic-scale details of the CdTe(111)/Si(001) interface were recorded. The layer quality depended upon the substrate tilt parameters, including the off-cut orientation angle and the azimuthal angle relative to [110]. Small (4 or 10) values of the latter angle gave high densities of stacking fault twins throughout the epilayer, whereas larger misorientation angles led to a rapid decrease away from the substrate. Under optimized growth conditions, the occurrence of twins effectively fell to zero within a distance of less than 2.5 from the substrate surface.

D.J.Smith, S.C.Y.Tsen, Y.P.Chen, J.P.Faurie, S.Sivananthan: Applied Physics Letters, 1995, 67[11], 1591-3