Device structure for providing improved Schottky barrier rectifier

摘要

This invention discloses a Schottky barrier rectifier formed in a semiconductor chip of a first conductivity type having a cathode electrode connected thereto near a bottom surface of the semiconductor chip. The Schottky rectifier further includes an epitaxial layer of the first conductivity type of a reduced doping concentration than the semiconductor chip near a top surface of the semiconductor chip. The Schottky rectifier further includes a high resistivity region disposed near peripheral edges of the semiconductor chip containing a reduced dopant concentration than the epitaxial layer. The Schottky rectifier further includes an anode electrode defined by a conductive layer disposed on top over the epitaxial layer wherein the conductive layer having all peripheral edges disposed on top of the high resistivity region. In a preferred embodiment, e.g., the rectifier further includes a barrier height reduction region disposed below the anode electrode disposed at a distance away from the high resistivity region. The barrier height reduction region containing a higher dopant concentration than the epitaxial layer for reducing the barrier height and for reducing a forward resistance of the Schottky rectifier.