Abstract: Various semiconductor wafers and their methods of fabrication are disclosed. One exemplary process comprises, forming a layer consisting essentially of aluminum nitride on a first wafer. The first wafer includes a substrate. The process also comprises bonding a second wafer to the first wafer. The aluminum nitride layer is interposed between the substrate and the second wafer after the bonding step. The process also comprises separating the first and second wafers to form a semiconductor on insulator (SOI) wafer. The SOI receives a layer of semiconductor material from the second wafer during the separating step. The SOI wafer includes the layer of semiconductor material, the layer consisting essentially of aluminum nitride, and the substrate after the separating step.