Abstract: A three mask process is described for a low voltage, low on-resistance power MOSFET. A serpentine gate divides a non-epi silicon die into laterally separated drain and source regions with a very large channel width per unit area.

Abstract: A termination structure and reduced mask process for its manufacture for either a FRED device or any power semiconductor device comprises at least two concentric diffusion guard rings and two spaced silicon dioxide rings used in the definition of the two guard rings. A first metal ring overlies and contacts the outermost diffusion. A second metal ring which acts as a field plate contacts the second diffusion and overlaps the outermost oxide ring. A third metal ring, which acts as a field plate, is a continuous portion of the active area top contact and overlaps the second oxide ring. The termination is useful for high voltage (of the order of 1200 volt) devices. The rings are segments of a common aluminum or Palladium contact layer.

Abstract: A single mask process for manufacture of a FRED employs a thick oxide layer over an N type silicon surface and a thin nitride layer over the oxide. A single mask defines FRED device spaced P diffusions. The oxide spanning the P diffusions is laterally etched away, under the nitride layer to expose the surface of adjacent P diffusions and the spanning N type silicon surface. All nitride is then removed and a top contact layer of aluminum is applied atop the silicon surface, contacting a P guard ring diffusion; the surface of the P diffusions defining PN junctions; and the top of the N silicon to define a Schottky diode contact.