Some embodiments relate to a semiconductor device that includes a body region of a field effect transistor structure formed in a semiconductor substrate between a drift region of the field effect transistor structure and a source region of the field effect transistor structure. The semiconductor substrate includes chalcogen atoms at an atom concentration of less than 1×1013 cm−3 at a p-n junction between the body region and the drift region, and at least part of the source region includes chalcogen atoms at an atom concentration of greater than 1×1014 cm−3. Additional semiconductor device embodiments and corresponding methods of manufacture are described.