US Patent 7273771 Common MOSFET process for plural devices

A core process is described for the manufacture of a Schottky, MOSFET or Accufet, using a plurality of identical manufacturing steps, including spaced trenches, in a single production line, with the device type to be produced being defined at an implant and diffusion stage for forming very low concentration mesas for a Schottky; higher concentration mesas with source regions for Accufet devices and a channel implant and source implant for a vertical conduction MOSFET.