A novel self-aligned polycrystalline silicon thin-film transistor using silicide layers

A novel self-aligned polycrystalline silicon (poly-Si) thin-film transistor (TFT) was fabricated using the three layers of poly-Si, silicon-nitride, and thin amorphous silicon. Gate and source/drain silicide formation was carried out simultaneously following silicon nitride and amorphous silicon patterning, enabling the use of only two mask steps for the TFT. The fabricated poly-Si TFT using laser annealed poly-Si exhibited a field-effect mobility of 30.6 cm
²
/Vs, threshold voltage of 0.5 V, subthreshold slope of 1.9 V/dec., on/off current ratio of /spl sim/10
⁶
, and off-state leakage current of 7.88×10/sup -12/ A/μm at the drain voltage of 5 V and gate voltage of -10 V.