GRAZING-INCIDENCE DIFFRACTION BY EPITAXIAL MULTILAYERED GRATINGS

Multilayered gratings have been investigated by high-resolution grazin g incidence diffraction, employing noncoplanar triple crystal diffract ometry. A theoretical treatment has been developed based on the distor ted wave Born approximation for multilayer diffraction. Grazing incide nce diffraction reveals as an optimal complement to symmetrical and as ymmetrical high-resolution X-ray diffraction. The method allows to mea sure separately the influences of the lateral strain and the grating s hape. Depth selective studies have been performed by surface gratings and buried gratings showing for the first time the evolution of the st rain relaxation phenomena in strained InGaAsP surface gratings resulti ng from burying in InP. (C) 1998 Published by Elsevier Science B.V. Al l rights reserved.