Patent ID: 8247295
Filing Date: 2012-08-21
Classification: H01L

Abstract:
1. A method for manufacturing a DMOS type semiconductor device, comprising: providing a silicon substrate; diffusively forming a buried diffusion layer on a main surface of the silicon substrate; forming an eptaxial growth layer on the silicon substrate and the buried diffusion layer; forming an isolation oxide layer on the epitaxial growth layer with an ion implantation opening; forming a gate oxide film on the epitaxial growth layer within the ion implantation opening; forming a gate on the gate oxide film; diffusively forming a body layer in the epitaxial growth layer by implanting ions of an impurity element having a first conduction type from the ion implantation opening; diffusively forming a regulation layer in the body layer by implanting ions of an impurity element having a second conduction type opposite to the first conduction type from the ion implantation opening, the regulation layer being shallower than the body layer; and diffusively forming a source layer in the regulation layer by implanting ions of an impurity element having the second conduction type from the ion implantation opening, wherein the source layer is formed within the regulation layer which is formed so as to horizontally extend beyond a region in which a gate bird's beak occurs due to thermal oxidation treatment performed after the body layer is formed and extends from an end of the gate which is formed on the gate oxide film toward underlying layers of the gate, the gate bird's beak in which a thickness and a shape of the gate oxide film are unstable.