High-performance fully depleted silicon-on-insulator transistors

Thin single-crystal silicon-on-insulator films with defect densities as low as 8*10/sup 5/ dislocations/cm/sup 2/ were formed by implantation of 1.5*10/sup 18/ O/sup +//cm/sup 2/ at 150 kV into bare silicon and annealing at 1350 degrees C for 6 h in nitrogen. Thin-film submicrometer MOS transistors were fabricated with self-aligned TiSi/sub 2/ fully covering sources, drains, and gates, and with p/sup +/ and n/sup +/ polysilicon gates for PMOS and NMOS transistors, respectively, but without a lightly doped drain. Transistors with gate lengths as short as 0.4 mu m exhibited essentially long-channel behavior with no kink and with a high saturation current. The device physics was investigated using PISCES simulations, which agreed well with the experimental results. A ring-oscillator stage delay of 58 ps was obtained for 1.0- mu m gate length CMOS circuits operating at 5 V.<
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