A fast X-ray method to determine Ge content and relaxation of partly relaxed Si1–xGex layers on silicon substrates

A fast X-ray method is presented to determine the Ge content and the relaxation of partly relaxed SiGe layers on Si substrates using a conventional powder diffractometer. The lattice parameters of the layer parallel and normal to the (001) substrate surface are obtained by a usual ω-2θ scan with symmetrical 004 reflection and an ω scan in asymmetrical reflection to measure the relative misorientation between inclined net planes of substrate and layer. The accuracy of this method is checked at a sample with pseudomorphic SiGe layer and its application is demonstrated at three partly relaxed samples with medium Ge content.