Semiconductor device structure and method for forming the same

A method for forming a semiconductor device structure, comprising:

• forming a fin structure over a substrate;
• forming a dummy gate structure across the fin structure;
• forming a first source/drain epitaxial structure beside the dummy gate structure in a first region of the substrate;
• forming a second source/drain epitaxial structure beside the dummy gate structure in a second region of the substrate;
• depositing a spacer layer over the first source/drain epitaxial structure and the second source/drain epitaxial structure;
• recessing the spacer layer, the first source/drain epitaxial structure, and the second source/drain epitaxial structure;
• forming a silicide structure over the first source/drain epitaxial structure and the second source/drain epitaxial structure;
• and
• forming a contact structure over the silicide structure.

A semiconductor device structure, comprising:

• nanostructures formed over a substrate;
• gate structures wrapped around the nanostructures;
• source/drain epitaxial structures formed over opposite sides of the nanostructures;
• a silicide structure formed in the source/drain epitaxial structures;
• a contact structure formed over the silicide structure,
• wherein a bottom surface of the silicide structure is lower than a top surface of a bottommost nanostructure.