HIGH-PERFORMANCE SUB-0.1 MU-M SILICON N-METAL OXIDE SEMICONDUCTOR TRANSISTORS WITH COMPOSITE METAL POLYSILICON GATES

A new fabrication process for sub-0.1 mum silicon n-metal-oxide-semico nductor field effect transistors with composite metal/polysilicon gate s is described. Gate resistance is reduced below that of plain polysil icon or silicided gates, so that higher speed performance is obtained from shorter gate length devices. The process has resulted in 0.08 mum channel length ring oscillators with record per stage delays of 10.5 ps at 85 K and 13 ps at room temperature, and unity-current-gain cutof f frequencies of 119 GHz at 85 K and 93 GHz at 300 K. Record high tran sconductances of 1040 mS/mm at 85 K and 740 mS/mm at 300 K have been m easured in 0.05 mum channel length devices.