Patent ID: 7880166

Claim:
A rectifier device, which comprises: a n-type semiconductor substrate being a wafer; a top metal layer having a first side and a second side disposed above said semiconductor substrate; a backside layer disposed immediately below said semiconductor substrate, diffusion to said backside layer using same polarity species as said semiconductor substrate; one or more reduced p-n junction structures disposed between said top metal layer and said semiconductor substrate, wherein each of said reduced p-n junction structures has a thin film of first p-type doping on top of a second p-type doping and the doping concentration of said first p-type is higher than said second p-type to create an early termination at p-side such that a total charge within the depletion region of said p-n junction is reduced, wherein the interface between said top metal layer and said first p-type at p-side is an ohmic contact; and a plurality of edge termination structures formed proximate said first side and said second side of said top metal layer, and above said semiconductor substrate for protection purpose and sustaining high voltage.