Patent ID: 7754550
Filing Date: 2010-07-13
Classification: H01L

Abstract:
1. The process for forming a trench type Schottky device comprising the steps of forming spaced trenches into the surface of a substrate each trench including sidewalls and a bottom; growing and then removing a thin layer of oxide in said trench to define rounded corners in the bottom of said trenches; depositing a layer of polysilicon directly on said sidewalls and said bottom of each trench; oxidizing said layer of polysilicon using a thermal oxidation process to convert it into a layer of an oxide of a given thickness; continuing said thermal oxidation process to oxidize a thin more than 100 Å thick layer of said substrate after the oxidation of said layer of polysilicon improving adherence of said converted layer of oxide; filling said trenches with a layer of conductive polysilicon which is insulated from said substrate by said layer of oxide, and applying a Schottky contact to the top of said substrate and in contact with the tops of the mesas between said trenches and with said conductive polysilicon in said trenches.