Strained Si wafers made by layer transfer and Ge condensation methods were investigated by several X-ray diffraction techniques. From the reciprocal space map measurements, the angular distribution of the lattice plane was estimated to be 0.4°. X-ray microbeam diffraction showed that the size of the domains with different orientations is less than 2 μm 2 , and the existence of the strain in the substrate propagated through a buried oxide layer from the SiGe layer. In large-area X-ray topographs, two kinds of crosshatch patterns were observed, depending on the process used to manufacture the wafer.