Structural and electrical properties of MOCVD-cobalt silicide on p-Si0.83Ge0.17/Si(001)

Structural, chemical and electrical properties of cobalt silicide/p-Si0.83Ge0.17/Si(001) were investigated by various analytical methods. Analyses of the as-deposited cobalt silicide layers on p-Si0.83Ge0.17/n-Si(001) at the growth temperature Ts=650 °C by metal organic chemical vapor deposition (MOCVD) using cyclopentadienyl dicarbonyl cobalt (Co(η5-C5H5)(CO)2), revealed epitaxial CoSi2 phases, as well as C-containing high resistive phases. Rapid thermal annealing at elevated temperature of 800 °C increased the fraction of epitaxial CoSi2 phase by the reaction of the remaining SiGe layers with Co supplied from the top surface layer, resulting in the reduction in the sheet resistance from ≅230 (as-deposited) to ≅30 Ω/□.