US Patent 11973127 Semiconductor structure with source/drain structure having modified shape

Semiconductor structures and method for forming the same are provide. The semiconductor structure includes a fin structure protruding from a substrate and a gate structure formed across the fin structure. The semiconductor structure further includes an Arsenic-doped region formed in the fin structure and a source/drain structure formed over the Arsenic-doped region. In addition, a bottommost portion of the Arsenic-doped region is lower than a bottommost portion of the source/drain structure.