Planarized copper gate hydrogenated amorphous-silicon thin-film transistors for AM-LCD's

We report the first fabrication of inverted-staggered back-channel-etch hydrogenated amorphous-silicon (a-Si:H) thin-film transistors (TFT's) with a planarized Cu gate electrode, The Cu gate-planarized (GP) a-Si:H TFT's, incorporating benzocyclobutene and n-SiNx:H as a double-layer gate insulator, had a field-effect mobility of 0.75 cm(2)/V-s, a threshold voltage of 4.92 V, and a subthreshold swing (S) of 0.48 V/dec, These results demonstrate that the GP-TFT's can have an electrical performance comparable with the conventional TFT's without gate planarization, Thus, the gate planarization technology is suitable for application in large-area and high-resolution active-matrix liquid-crystal displays.