The present invention relates to a method for manufacturing semiconductor materials comprising epitaxial growing of group III-V materials, for example gallium arsenide (GaAs), on for example a non III-V group material like silicon (Si) substrates (wafers), and especially to pre-processing steps providing a location stabilization of dislocation faults in a surface layer of the non III-V material wafer in an orientation relative to an epitaxial material growing direction during growing of the III-V materials, wherein the location stabilized dislocation fault orientations provides a barrier against threading dislocations (stacking of faults) from being formed in the growing direction of the III-V materials during the epitaxial growth process.