Silicon-on-insulator m.o.s.f.e.t.s fabricated on laser-annealed polysilicon on SiO2

Abstract

N-channel-enhancement and light-depletion-mode m.o.s.f.e.t.s have been fabricated on laser-annealed 0.5 μm polysilicon films, deposited on 1 μm of SiO2 grown on single-crystal silicon substrates. Threshold voltages of 0.35–0.45 V and −0.5 – −0.7 V and surface mobilities of 170 cm2/Vs and 215 cm2/Vs were obtained on the enhancement and depletion devices, respectively. These results compare favourably with values realised in silicon-on-sapphire (s.o.s.) and bulk N-m.o.s. devices. In addition, the measured source-drain leakage currents match the best reported values for s.o.s. devices.