Process window control for gate formation in semiconductor devices

A method of fabricating a semiconductor structure, comprising:

• forming a cladding layer adjacent a first side, a second side, a third side, and a fourth side of an active channel structure;
• forming a recess by removing a portion of the cladding layer and a portion of the active channel structure such that after forming the recess the cladding layer is adjacent the first side, the second side, and the third side of the active channel structure, but not adjacent the fourth side of the active channel structure;
• filling the recess with dielectric material;
• and
• forming a gate structure around the active channel structure,
• wherein forming the cladding layer comprises forming a layer of silicon germanium adjacent the first side, the second side, the third side, and the fourth side of the active channel structure.

A method of fabricating a semiconductor structure, comprising:

• forming a cladding layer around an active channel structure;
• removing a portion of the cladding layer and a portion of the active channel structure after forming the cladding layer around the active channel structure;
• forming a gate structure around the active channel structure, wherein the gate structure comprises an active gate structure;
• forming a dummy gate structure around the active channel structure;
• and
• removing the dummy gate structure before forming the active gate structure.