Amorphous-silicon thin-film metal-oxide-semiconductor transistors

Two types of glow-discharged amorphous-silicon thin-film metal-oxide-semiconductor field-effect transistors (MOSFET’s) were fabricated. The N-channel enhancement-type FET, which has an undoped channel region, showed only a few hysteresis characteristics and, by changing the gate voltage, the drain current was changed from the order of pA to the order of 0.1 μA at Vd=20 V. The FET, which has a doped n layer at the channel region, operated in the depletion mode and its on-current was changed by changing the doping-gas concentration. It seems that the FET’s have various potential applications, especially for switching circuits used for display devices.