High-Mobility Bottom-Gate Thin-Film Transistors with Laser-Crystallized and Hydrogen-Radical-Annealed Polysilicon Films

High-performance bottom-gate thin-film transistors (TFTs) have been realized with excimer-laser-crystallized polysilicon films, for the first time. TFT characteristics were greatly dependent on the silicon film thickness as well as the pulsed-laser energy density. It was found also that posthydrogenation based on hydrogen-radical annealing improves the TFT characteristics drastically. The field-effect mobilities exceeded 220 cm 2 /Vs for electrons and 140 cm 2 /Vs for holes, respectively.