High performance 32nm SOI CMOS with high-k/metal gate and 0.149μm ² SRAM and ultra low-k back end with eleven levels of copper

Abstract

This work presents a 32 nm SOI CMOS technology featuring high-k/metal gate and an SRAM cell size of 0.149 μm2. Vmin operation down to 0.6 V in a 16Mb SRAM array test vehicle has been demonstrated. Aggressive ground rules are achieved with 193 nm immersion lithography. High performance is enabled by high-k/ metal gate plus innovation on strained silicon elements including embedded SiGe and dual stress liner (DSL). Gate lengths down to 25 nm have been demonstrated enabling performance without the power penalty from gate capacitance. AC drive currents of 1.55 mA/um and 1.22 mA/um have been achieved at an off-state of 100 nA/μm and VDD of 1 V for NFET and PFET, respectively. For the first time, we have also demonstrated that SOI maintains performance benefit over bulk silicon in high-k/metal gate and 32 nm ground rules.