Copper gate hydrogenated amorphous silicon TFT with thin buffer layers

We demonstrated a Cu gate hydrogenated amorphous silicon thin-film transistor (TFT) with buffer layers. We introduced an AlN/Cu/Al₂O₃ multilayer for a gate of an a-Si : H TFT. The Al₂O₃ improves the adhesion to glass substrate and AlN protect the Cu diffusion to the TFT and plasma damage to Cu during plasma enhanced chemical vapor deposition of silicon-nitride. An a-Si : H TFT with a Cu gate exhibited a field effect mobility of 1.18 cm²/Vs, a gate voltage swing of 0.87 V/dec., and a threshold voltage of 3.5 V.