Patent ID: 7029979

Claim:
A method for fabricating a semiconductor device comprising: depositing an isolation oxide layer and a first nitride layer on a semiconductor substrate; forming a trench in an active region by etching a portion of the first nitride layer and a portion of the isolation oxide layer to thereby expose the semiconductor substrate in the active region; growing an epitaxial layer on the active region and depositing a first oxide layer on the epitaxial layer; using a source/drain mask, etching a first portion of the first oxide layer such that a second portion of the first oxide layer having a predetermined thickness remains where a source and a drain are to be formed; removing the second portion of the first oxide layer where the source and the drain are to be formed and performing an epitaxial growth on the portions where the source and the drain are to be formed to thereby form the source and the drain; using a gate mask, etching a portion of the first oxide layer where a gate is to be formed; depositing a second nitride layer on the source, the drain and the exposed active region, and etching back the second nitride layer to thereby form a nitride layer to control a length of the gate; sequentially depositing a gate insulation layer and a gate electrode on the active region; and depositing a second oxide layer; and forming plugs on the source, the drain and the gate.