High-resolution triple-axis X-ray diffraction measurements were used to study strain relaxation in the individual layers of a SiGe/Si structure which was step-graded to pure Ge. The tilt of each layer was explained by extending a model, which had previously been proposed in order to obtain the nucleation activation energy of dislocations, so as to account for the reduced miscut of the growth surface as the sample relaxed. It was also applied to the variation in properties as a function of alloy composition.

P.M.Mooney, F.K.LeGoues, J.L.Jordan-Sweet: Applied Physics Letters, 1994, 65[22], 2845-7