Aggressively scaled (0.143 /spl mu/m/sup 2/) 6T-SRAM cell for the 32 nm node and beyond

A 0.143 /spl mu/m/sup 2/ 6T-SRAM cell has been fabricated using a planar SOI technology with mixed electron-beam and optical lithography. This is the smallest functional 6T-SRAM cell ever reported - consistent with cell areas beyond the 32 nm technology node. Enabling process features include a 25 nm SOI layer, shallow trench isolation (STI), 45 nm physical gates with ultra-narrow 15 nm spacers, novel extremely thin cobalt disilicide, 50 nm tungsten plug contacts, and damascene copper interconnects. Device threshold voltages (V/sub T/) and cell beta ratio (/spl beta/) are optimized for cell stability at these aggressive ground rules. The 0.143 /spl mu/m/sup 2/ 6T-SRAM cell exhibits a static noise margin (SNM) of 148 mV at V/sup DD/=1.0 V.