Patent ID: 8187939
Filing Date: 2012-05-29
Classification: H01L

Abstract:
1. A method for making a shield gate trench semiconductor device, comprising: a) applying a trench mask as a first mask to a semiconductor substrate; b) etching the semiconductor substrate to form trenches TR c) forming first conductive material at the bottom of the trenches TR d) forming a second conductive material over the first conductive material in the trenches TR forming a dielectric layer on top of the source electrode in the trenches TR chemical mechanical polishing and/or etching back the dielectric layer to a pre-determined thickness to form the inter-poly-dielectric layer; growing gate oxide on sidewalls of exposed portions of the trenches TR depositing the second conductive material into the trenches TR e) depositing a first insulator layer on top of the trenches TR f) forming a body layer in a top portion of the substrate; g) forming a source layer in a top portion of the body layer; h) applying a second insulator layer on top of the trenches TR i) applying a contact mask as a second mask on top of the second insulator laver; j) forming a source electrode contact in trench TR k) applying a metal mask as a third mask and forming source metal and gate metal on top of the second insulator layer.