Abstract: The present invention relates to a method of manufacturing a wafer comprising a single crystalline bulk substrate of a first material and at least one epitaxial layer of a second material which has a lattice different from the lattice of the first material. The present invention provides a method for manufacturing a wafer in which a layer which is lattice-mismatched with the substrate can be grown on the substrate with a high effectiveness and high quality at a low cost. A roughening step is included for roughening the surface of the bulk substrate and a growing step is included for growing the second material on the rough surface with a reduced number of threading dislocations and an enhanced strain relaxation compared to a second material that is epitaxially grown on a polished surface.