Semiconductor device structure and methods of forming the same

A method for forming a semiconductor device structure, comprising:

• forming a first fin structure in a first device region and a second fin structure in a second device region;
• forming a sacrificial gate structure across the first fin structure and the second fin structure;
• forming a gate spacer on opposite sidewalls of the sacrificial gate structure;
• and
• recessing the first fin structure and the second fin structure such that a top surface of each of the first fin structure and the second fin structure not covered by the sacrificial gate structure and the gate spacer has a slope gradually decreasing in a direction away from the sacrificial gate structure.

A semiconductor device structure, comprising:

• a first source/drain feature disposed in a first device region;
• a first conductive feature disposed over the first source/drain feature;
• a first fin structure disposed in the first device region and in contact with the first source/drain feature;
• a first gate structure disposed over the first fin structure and having a bottom extended a first distance into the first fin structure;
• a second fin structure disposed in a second device region;
• a second gate structure disposed over the second fin structure and having a bottom extended a second distance into the second fin structure, wherein the first distance is different than the second distance;
• a contact etch stop layer (CESL) disposed over the first source/drain feature;
• and
• a contact sidewall dielectric layer disposed between the CESL and the first conductive feature above the first source/drain feature.