A HIGH-PERFORMANCE POLYCRYSTALLINE SILICON THIN-FILM-TRANSISTOR WITH A SILICON-NITRIDE GATE INSULATOR

We have fabricated a high performance polycrystalline silicon (poly-Si ) thin film transistor (TFT) with a silicon-nitride (SiNX) gate insula tor using three stacked layers: very thin layer of hydrogenated amorph ous silicon (a-Si:H), SiNX and laser annealed poly-Si. lifter patterni ng thin a-Si:H/SiNX layers, gate, and source/drain regions were ion-do ped and then Ni layer were deposited, Such structure was annealed at 2 50 degrees C to form NiSi silicide phase. The low resistive NiSi silic ides were introduced as gate/source/drain electrodes in order to reduc e the process steps. The poly-Si with a grain size of 250 nm and low r esistance n(+) poly-Si for ohlnic contact were introduced to have a hi gh performance TFT. The fabricated poly-Si TFT exhibited a field effec t mobility of 262 cm(2)/Vs and a threshold voltage of 1 V.