Observation of strain relaxation phenomena in buried and nonburied III-V surface gratings through high resolution x-ray diffraction

We present high-resolution x-ray diffraction studies describing the evolution of the strain relaxation phenomena in a strained InGaAsP surface grating resulting from burying in InP. We have compared reciprocal space maps of symmetrical and asymmetrical reflections from free-strain gratings, strained surface gratings, and strained buried gratings. After burying, modifications in the coherently and diffusely scattered intensity have been observed indicating the counteraction of the embedding material to the laterally nonuniform strain relaxation, which occurs in free-surface (nonburied) strained grating. (C) 1997 American Institute of Physics.