Methods of forming power semiconductor devices having laterally extending base shielding regions

摘要

Methods of forming power semiconductor devices include forming a semiconductor substrate having a drift region of first conductivity type therein and a transition region of first conductivity type that extends between the drift region and a first surface of the semiconductor substrate. A gate electrode is formed on the first surface. Base and base shielding region dopants are implanted into the transition region using the gate electrode as an implant mask. A plurality of annealing steps are performed so that the base shielding region dopants are driven in laterally and vertically to substantially their full and final depth within the substrate and thereby define first and second base shielding regions that constrict a neck of the transition region to a minimum width.