Aggressively Scaled Strained-Silicon-on-Insulator Undoped-Body High- $\kappa$ /Metal-Gate nFinFETs for High-Performance Logic Applications

Strained-silicon-on-insulator (SSOI) undoped-body high-κ /metal-gate n-channel fin-shaped field-effect transistors (nFinFETs) at scaled gate lengths and pitches (i.e.,L_GATE ~ 25 nm and a contacted gate pitch of 130 nm) were fabricated using a gate-first flow. A “long and narrow” fin layout (i.e., fin length ~ 1 μm) was leveraged to preserve uniaxial tensile strain in the transistors. These devices exhibit drive currents suitable for high-performance logic technology. The change in the slope of R_ON - L_GATE (dR_ON/dL_GATE), transconductance G_MSAT, and injection velocity (v_inj) measurements indicate a ~ 15% mobility-induced I_ON enhancement with SSOI relative to SOI nFinFETs at ultrashort gate lengths. Raman measurements conducted on SSOI substrates after fin formation demonstrate the preservation of ~ 1.3-GPa uniaxial tensile strain even after 1100°C annealing.