A new non-destructive measurement method for characterization of Si1 − xGex based multi-layer structures, including SiGe epitaxial layer and the adjacent strained Si epitaxial layer, has been developed. The method is based on a small signal surface photo-voltage technique and allows measurement of germanium concentration and thickness of top epitaxial layer. A new physical model and a measurement algorithm were developed. The results of the measurement of a set of SiGe samples with various germanium concentration and silicon layer thickness values are presented. The characteristic mixed crystal parameter—the coefficient representing the energy gap dependence on Ge content was calculated.
