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

Kingsuk Maitra,Nancy R Klymko,Robert J Miller,Huiming Bu,Hemant Adhikari,Ali Khakifirooz,James O'Neil,Chun-Chen Yeh,Pranita Kulkarni,Hemanth Jagannathan,Effendi Leobundung,Veeraraghavan S Basker,Bruce Doris,Dale Mcherron,Theodorus Standaert,Katherine Saenger,Jonathan Faltermeier,Vamsi K Paruchuri

doi:10.1109/led.2011.2126556

Abstract

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.

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