Tungsten plug drain extension

摘要

A power metal-oxide-semiconductor field effect transistor (MOSFET) cell includes a semiconductor substrate. A first electrode is disposed on the semiconductor substrate. A voltage sustaining layer is formed on the semiconductor substrate. A highly doped active zone of a first conductivity type is formed in the voltage sustaining layer opposite the semiconductor substrate. The highly doped active zone has a central aperture and a channel region that is generally centrally located within the central aperture. A terminal region of the second conductivity type is disposed in the voltage sustaining layer proximate the highly doped active zone. The terminal region has a central aperture with an opening dimension generally greater than an opening dimension of the central aperture of the highly doped zone. An extension region is disposed in the voltage sustaining region within the central aperture of the highly doped active zone.