High-resolution X-ray diffractometry and topographical methods were used to investigate the lateral uniformity and structural properties of (Cd,Hg)Te layers which had been grown, via metalorganic vapor-phase epitaxy, onto CdTe buffer layers on GaAs. A clear correlation was observed between rocking curve widths, lattice tilts and the density of pyramid-like surface defects. The latter were also associated with an increased twin density. Upon rotating the sample about its surface normal, the 400 surface symmetrical rocking curve width varied by up to an order of magnitude. This suggested that lattice tilt played an important role in broadening the rocking curve. The X-ray topographical data revealed the presence of large tilt boundaries in the epilayer, which were related to the dislocation structure in the GaAs substrate.

A.M.Keir, A.Graham, S.J.Barnett, J.Giess, M.G.Astles, S.J.C.Irvine: Journal of Crystal Growth, 1990, 101[1-4], 572-8