Power MOSFET

摘要

A power MOSFET having at least one protection ring (14) surrounding the edge of the MOSFET, in which in a semiconductor body (2,3) of one conductivity type, at least one highly doped zone (16) of one conductivity type is embedded in a trench (17) of the other conductivity type as a protection ring (14). For locating the dopant material for the highly doped zone (16) a hole (25) inserted into one layer (12) has only one width such during an oxidation process following the doping of the highly doped zone (16), the hole (25) becomes blocked, but one cell opening (24) to the MOSFET remains open. The hole (25) specifically has a width of 0.1 to 1.0 mu m.