Patent ID: 8273620

Claim:
A method for fabricating a semiconductor device comprising: defining a cell active region in a cell region of a semiconductor substrate and defining a peripheral active region in a peripheral region of the semiconductor substrate by forming isolation regions in the cell region and the peripheral region; forming a first gate stack on the cell active region and a second gate stack on the peripheral active region; and, forming a cell epitaxial layer on an exposed portion of the cell active region and forming a peripheral epitaxial layer on an exposed portion of the peripheral active region by performing at least one selective epitaxial growth process on the semiconductor substrate, wherein the peripheral epitaxial layer has a greater height than the cell epitaxial layer, the cell epitaxial layer comprises an extending portion and the extending portion of the cell epitaxial layer is formed on a first isolation region of the isolation regions, the peripheral epitaxial layer comprises an extending portion, the extending portion of the peripheral epitaxial layer is formed on a second isolation region of the isolation regions, and a horizontal length of the extending portion of the cell epitaxial layer is shorter than a horizontal length of the extending portion of the peripheral epitaxial layer.