Gt. Sarcona et al., Polysilicon thin-film transistors using self-aligned cobalt and nickel silicide source and drain contacts, IEEE ELEC D, 20(7), 1999, pp. 332-334
Polysilicon thin-film transistors (TFT's) with island thickness of 20 and 7
0 nm were fabricated with self-aligned cobalt and nickel silicide contacts
to the source and drain. The silicide contacts are shown to reduce the seri
es resistance, which limits the on-current of the device, thus significantl
y increasing the effective mobility in the 20-nm island devices. The mobili
ties of 20-nm cobalt and nickel silicided devices are similar to those with
70-nm islands, 31 versus 33 cm(2)/V-s, whereas the nonsilicided 20-nm devi
ces have a mobility of only 13 cm(2)/V-s, The island thickness is shown to
influence other device parameters affecting active matrix display driver ci
rcuit design, such as threshold voltage, leakage current, and subthreshold
swing; all these parameters are improved when the island thickness is decre
ased.