Abstract of the Disclosure

A planar high power Metal-Oxide-Semiconductor-Field-Effect-Transistor (MOSFET) including a substrate with an epitaxial layer on a surface thereof. A gate electrode including a strip of metal extending across a surface of the epitaxial layer and having a plurality of fingers extending therefrom along its length. The gate electrode being electrically insulated from the epitaxial layer by a layer of oxide. A source electrode in the surface of the epitaxial layer including fingers extending therefrom and interdigitating with the fingers of the gate electrode. There are p and n diffusion regions formed in the epitaxial layer except in an area under each of the gate fingers, which area remains undiffused. A drain electrode is connected to the surface of the substrate opposed to the surface upon which the epitaxial layer is deposited.

During operation of the MOSFET as the blocking voltage across the transistor increases and the transistor is in the OFF state, the horizontal components of fields from the adjacent and closely spaced p-regions cancel each other so that voltage breakdown due to junction curvature is avoided

• illustrates a step in a method for manufacturing the transistor of the present invention.

 Citations [54]:
  
3,484,865  12/1969  Nienhuis
3,515,405  05/1970  Carlson
4,129,879  12/1978  Tantraporn et al