Abstract: The electronic semiconductor component has a crystalline wafer substrate with an active surface and a semiconductor layer coating the active surface. So that the semiconductor layer has a few surface defects the crystalline wafer substrate is a sapphire or silicon carbide single crystal and the active surface has a pit density of less than 500 pit/cm2, preferably less than 100 pit/cm2. The polishing method for obtaining the active surface with these pit densities includes polishing with a polishing agent, such as a silicon suspension, and a polishing tool, which is pressed on the active surface with a pressure of preferably from 0.05 to 0.2 kg/cm2 and moved over the active surface with polishing motions distributed statistically and uniformly over a 360° angle during polishing.

Abstract: The method of making an especially low-stress wafer substrate with an active surface to be coated with few surface defects that produce coating defects includes polishing the active surface with the help of a polishing tool in order to smooth it and changing a polishing direction of the polishing tool performing the polishing over the active surface so that each site or location on the surface is polished with polishing motions distributed statistically and uniformly over a 360° angle.