Suicides have been used in industry since minimum dimensions reached the 1 ~tm node. The goal of this project is to explore Titanium and Cobalt Silicide and incorporate its use into the JUT sub-micron CMOS process. TiSi2 had been the industry standard to decrease this resistivity through the 0.25μm node. The current industry standard is CoSi2, with resistivity independent of its grain size. This allows for the smaller dimensions. However, CoSi2 formation is very sensitive to oxygen contamination. A Ti capping layer may minimize the contamination by reacting with any oxygen. The nitrogen implant prior to metal deposition should suppress agglomeration in the films and improve thermal stability. A Transmission Line Model (TLM) structure has been used to extract specific contact resistivity and contact resistance for the suicide. Four point probing will measure the resistivity of the polycide. Results show a reduction in sheet resistance of polysilicon samples after silicidation. RBS and XRD analyses show oxygen contamination.
"TiSi2 and CoSi2 Silicide Formation Using N2+ Implant,"
Journal of the Microelectronic Engineering Conference: Vol. 13
, Article 13.
Available at: http://scholarworks.rit.edu/ritamec/vol13/iss1/13