Semiconductor integrated circuit device and related fabrication method

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.