Semiconductor device and method of manufacturing the same

A semiconductor device comprising:

• a first MOSFET including:
• a first gate electrode formed on a first semiconductor layer in a first region of a semiconductor substrate;
• a first channel region formed immediately below said first gate electrode in the first semiconductor layer;
• a first diffusion layer constituting source/drain regions formed at both the sides of said first channel region in the first semiconductor layer;
• a first epitaxial layer formed on said first diffusion layer;
• and
• a first silicide layer formed on said first epitaxial layer;
• and
• a second MOSFET including:
• a second gate electrode formed on a second semiconductor layer in a second region of the semiconductor substrate;
• a second channel region formed immediately below said second gate electrode in the second semiconductor layer;
• a second diffusion layer constituting source/drain regions formed at both the sides of said second channel region in the second semiconductor layer;
• a second epitaxial layer, which is thinner than said first epitaxial layer, formed on said second diffusion layer;
• and
• a second silicide layer formed on said second epitaxial layer.

A semiconductor device comprising:

• a first MOSFET including:
• a first gate electrode formed on a first semiconductor layer in a first region of a semiconductor substrate;
• a first channel region formed immediately below said first gate electrode in the first semiconductor layer;
• a first diffusion layer constituting source/drain regions formed at both the sides of said first channel region in the first semiconductor layer;
• a first epitaxial layer formed on said first diffusion layer;
• and
• a first silicide layer formed on said first epitaxial layer;
• and
• a second MOSFET including:
• a second gate electrode formed on a second semiconductor layer in a second region of the semiconductor substrate;
• a second channel region formed immediately below said second gate electrode in the second semiconductor layer;
• a second diffusion layer constituting source/drain regions formed at both the sides of said second channel region in the second semiconductor layer;
• and
• a second silicide layer formed on said second diffusion layer,
• wherein said first region is an SOI region, and said second region is a bulk region.