Impact of NiPt Thickness Scaling on Contact Resistance From Thin-Body FD SOI to Trigate FETs

The impact of NiPt thickness scaling on total resistance is investigated using short-channel (L_g = 40 nm) nm high-k metal-gate complementary SOI MOSFETs with fin widths varying from 500 nm ("planar single-gate thin-body FD SOI FET") to 25 nm (trigate FET). It is shown that limiting the amount of NiPt available for silicidation becomes increasingly critical as fin width scales due to a reduced silicide-to-silicon interfacial contact area and facilitated silicide encroachment toward the channel. The prevention of Schottky contact by scaling NiPt thickness from 10 to 5 nm on a 20-nm-thick SOI enabled a >; 2 × (NFET) and >; 6 × (PFET) reduction in total resistance along with swing and DIBL improvements on trigate FETs.