Patent ID: 7642159
Filing Date: 2010-01-05
Classification: H01L

Abstract:
1. A method comprising: sequentially forming an oxide layer, a nitride layer and a photoresist film on a semiconductor substrate, wherein the first photoresist is formed directly on and contacting the nitride layer; simultaneously removing a portion of the nitride layer and the oxide layer using the first photoresist film as a mask to expose a portion of the semiconductor substrate; forming a wet oxide layer on the exposed portion of the semiconductor substrate and contacting sidewalls of the oxide layer and the nitride layer; forming a recessed surface in the exposed portion of the semiconductor substrate by removing the wet oxide layer; forming a gate insulating layer on the recessed surface of the semiconductor substrate; forming a gate electrode over the gate insulating layer; and forming sidewall on sides of the gate electrode and the gate insulating layer such that the uppermost surface of the sidewalls are coplanar with the uppermost surface of the gate electrode; implanting dopants on both sides of the gate electrode to form a source/drain area.