Asymmetric Electrical Properties of Half Corbino Hydrogenated Amorphous Silicon Thin-Film Transistor and Its Applications to Flat Panel Displays

Abstract

The half-Corbino hydrogenated amorphous silicon (a-Si:H) thin-film transistors (TFTs) were fabricated with a five-photomask process used in the processing of the active matrix liquid-crystal displays (AM-LCD). We showed that the a-Si:H half-Corbino TFTs have the asymmetric electrical characteristics under different drain-bias conditions. In comparison to half-Corbino TFT with unpatterned gate electrode, the device parasitic capacitance can be significantly reduced by patterning the gate electrode for same device dimension, while the sub-threshold swing and threshold voltage remain identical for same bias condition. The OFF-current remains below 0.1 pA for all device configurations. Finally, we discuss their potential applications as a driving or switching TFT to various flat panel displays.