Novel Aluminum Segregation at NiSi/ ${p}^{+}$-Si Source/Drain Contact for Drive Current Enhancement in $P$-Channel FinFETs

This letter reports the first demonstration of the integration of nickel-silicide (NiSi) source/drain (S/D) contact technology with a novel aluminum (Al) segregation at the NiSi/p ⁺-Si interface in the S/D of p-channel FinFETs to reduce contact resistance. This leads to reduction in parasitic series resistance. We show that the addition of a low-dose (2times10¹⁴ atom/cm²) Al ion implant step in the Si S/D of p-channel FinFETs could achieve ~ 19% enhancement in drive current. This is attributed to the reduction in effective Schottky barrier height of holes at NiSi/p⁺-Si interface, from ~ 0.4 to ~ 0.12 eV, using Al segregation.