High performance FDSOI CMOS technology with metal gate and high-k

Abstract

A high performance FDSOI CMOS technology featuring metal gate electrodes and high-k gate dielectrics is presented. Work-function tuning is accomplished by materials and process modification to achieve appropriate threshold voltages for FDSOI CMOS. The gate stacks exhibit an extremely thin effective inversion thickness (T/sub inv/) down to 14A with a gate leakage current of 0.2A/cm/sup 2/. This represents a six order of magnitude leakage reduction compared to Poly/SiO/sub 2/. By optimizing the gate stack, the highest unstrained electron mobility is realized (207cm/sup 2/A/s at E/sub eff/=1Mv/cm) at T/sub inv/=14A. Drive currents of 1050/spl mu/A//spl mu/m and 770/spl mu/A//spl mu/m at I/sub off/ of 90nA//spl mu/m and 28nA//spl mu/m are achieved for nMOS and pMOS respectively. This is the highest reported pFET drive current for metal gate transistors with high-k gate dielectrics. We also present FDSOI metal gate high-k ring oscillators and SRAM cells with static noise margin (SNM) of 328mV at V/sub dd/=1,2V.