Thin channel a-Si:H thin film transistors

Summary form only given. One serious problem for active matrix liquid crystal displays (AMLCDs) is the throughput of the equipment used to deposit the hydrogenated amorphous silicon (a-Si:H) thin film transistor (TFT) active material. One approach to improving throughput would be to decrease the active layer thickness. However, thicknesses below /spl sim/50-70 nm have been avoided due to observed degradation of device saturation current. We have investigated the performance of ultra-thin TFTs by modeling devices of varying thickness and have fabricated ultra-thin a-Si:H TFTs suitable for use in AMLCDs. The ultra-thin active layer TFT structure described can provide improved throughput, simplified processing, higher channel conductance, and current saturation characteristics equal to or better than current devices. In addition, fabrication of thin channel layer devices with doped contact regions is also possible and is directly compatible with commonly used a-Si:H TFT AMLCD processing.