Formation of erbium-silicide as source and drain for decananometer-scale Schottky barrier metal-oxide-semiconductor field-effect transistors

Erbium-silicide (ErSi1.7) is formed on silicon-on-insulator (SOI) by using a rapid thermal annealing (RTA) technique. Annealing temperature and time are 500 °C and 5 min, respectively. The formation of ErSi1.7 phase is confirmed by X-ray diffraction and Auger electron spectroscopy analysis. Also, the growth mechanisms of ErSi1.7 with the variation of the SOI thickness are investigated and the proper thickness condition between erbium and SOI is determined for the stable growth of ErSi1.7. The sheet resistance of ErSi1.7 is less than 30 Ω/sq even if the line width is <100 nm. Thus, ErSi1.7 is applicable in decananometer-scale Schottky barrier metal-oxide-semiconductor field-effect transistors (SB-MOSFETs). The manufactured 50 nm gate length n-type SB-MOSFET shows excellent transistor characteristics with large on/off current ratio and low leakage current, which shows the possible applicability of ErSi1.7 as source and drain junction in decananometer-scale n-type SB-MOSFETs.