A 0.25- m, 600-MHz, 1.5-V, Fully Depleted SOI CMOS 64-Bit Microprocessor

A 0.25m, four-layer-metal, 1.5-V, 600-MHz, fully depleted (FD) silicon-on-insulator (SOI) CMOS 64-bit ALPHA1 microprocessor integrating 9.66 million transistors on a 209-mm silicon die has been developed leveraging the existing bulk design. FD-SOI technology is used because it has better immunity for dynamic leakage current than partially depleted SOI in highspeed dynamic circuits without body contact. C–V characteristics of metal-oxide-silicon-oxide-silicon with and without source-drain junctions are described to explain the behavior of FD-SOI transistor. Race, speed, and dynamic stability have been simulated to reassure the circuit operation. Key process features are shallow trench isolation, 4-nm gate oxide, 30-nm co-silicide, 46-nm silicon film, and 200-nm buried oxide. The FD-SOI microprocessor runs 30% faster than that of bulk, and it passes the reliability and system test.