The lattice deformation of strained InGaP layers which were grown on InAlAs or InP layers was studied by using 2 types of channelling technique. One method was to analyze angular scans of the <110> directions which exhibited lattice strain and relaxation. The other method was to make de-channelling probability measurements. The types and densities of the structural defects were estimated from the energy dependences of the de-channelling probabilities in the (011) planes and <100> axes. The results indicated that InGaP layers which were grown on InAlAs, with a 1% lattice mismatch, were subjected to tetragonal distortion; even when the thickness exceeded the critical thickness and misfit dislocations were generated at the InGaP/InAlAs interfaces. When the thickness was increased further, and cross-hatched patterns appeared, the lattice began to relax. On the other hand, the lattice of an InGaP layer which was deposited on InP, with the same lattice mismatch (1%), exhibited relaxation and point defects and planar defects were found to be present.

C.Nozaki, T.Noda, S.Fujita, Y.Ashizawa: Journal of Crystal Growth, 1994, 145[1-4], 164-70