Patent ID: 8551867
Filing Date: 2013-10-08
Classification: H01L

Abstract:
1. A method of manufacturing a mesa edge shielding trench Schottky rectifier, comprising the steps of: (A) forming an epitaxial layer grown on a first surface of a semiconductor substrate; (B) forming a plurality of trenches spaced from each other and extended into the epitaxial layer, wherein an epitaxial region between two adjacent trenches forms a silicon mesa; (C) forming a polysilicon region, having a T-shape, that is separated from an inner wall of each of the trenches and a top surface of the epitaxial layer by a layer of dielectric material, wherein a coronal upper portion of the polysilicon region is higher than the epitaxial layer, a width of the coronal upper portion of the polysilicon region is bigger than a width of each of the trenches; (D) forming an anode electrode by depositing a layer of metal on an entire structure, thus forming an ohmic contact on a top surface of the polysilicon region and a Schottky contact on an exposed surface of the epitaxial layer; (E) forming a cathode electrode by depositing a layer of metal on an opposite surface of the semiconductor substrate, thus forming an ohmic contact thereon; and (F) forming a pair of dielectric spacer regions on the epitaxial layer, comprising: wherein each of the pair of dielectric spacer regions covers a sidewall of the layer of dielectric material.