CMOS on buried nitride—A VLSI SOI technology

A CMOS technology in silicon on insulator (SOI) for VLSI applications is presented. The insulator is a buried silicon nitride formed by nitrogen implantation and annealing. The CMOS devices are fabricated in the superficial monocrystalline silicon layer without an epitaxial process, 1-µm PMOS and 2-µm NMOS transistors have been realized, which have been used to built inverters, ring Oscillators, and other circuits. With 40-nm gate oxide the transistors withstand gate and drain voltages of 10 V. Mobilities, subthreshold behavior, and leakage currents are nearly the same as in bulk-CMOS devices. Ring-oscillator measurements yield inverter delay times of 230 ps and power delay products of 14 fJ.