Low off-state leakage current thin-film transistor using Cl incorporated hydrogenated amorphous silicon

Abstract

We have studied the fabrication of low off-state leakage current amorphous silicon thin-film transistor (TFT) using Cl incorporated amorphous silicon [a-Si:H(:Cl)] as an active layer. The room temperature conductivity and conductivity activation energy of a-Si:H(:Cl) deposited by adding 10% SiH2Cl2 into silane plasma are much less than those of undoped hydrogenated amorphous silicon because the a-Si:H(:Cl) shows a p-type conduction. The off-state leakage currents of the a-Si:H(:Cl) TFT under light illumination are much less than that of conventional a-Si:H TFT without degrading the field effect mobility because the photoconductivity of a-Si:H(:Cl) is much less than that of a-Si:H.