Patent ID: 7368337
Filing Date: 2008-05-06
Classification: H01L

Abstract:
1. A method of manufacturing a semiconductor device, comprising: forming a first well by implanting ions into a semiconductor substrate; forming a first gate insulation layer on the semiconductor substrate; forming a first polysilicon layer on the first gate insulation layer; forming a gate electrode, a first source electrode, and a first drain electrode by patterning the first polysilicon layer; forming a first source region and a first drain region by ion implantation using the gate electrode, the first source electrode, and the first drain electrode as implantation masks; forming a second gate insulation layer on the gate electrode; forming an insulating layer on the entire surface over the semiconductor substrate; forming a source trench and a drain trench by etching the insulating layer, wherein the insulating layer is partially etched to remain over the first source electrode for forming the source trench and the insulating layer is etched to an upper surface of the first drain electrode for forming the drain trench; forming a second source electrode and a second drain electrode by filling the source trench and the drain trench with a second polysilicon layer, wherein the second drain electrode is faced to the first drain electrode for forming a single drain electrode; forming a second source region and a second drain region by patterning a third polysilicon layer on an exposed region of the insulating layer and implanting ions into the third polysilicon layer; and forming a second well by forming a silicon layer on the entire surface over the semiconductor substrate and sequentially implanting ions into the silicon layer.