Co-Induced Low-Temperature Silicidation of Ni Germanosilicide Using NiPt Alloy and the Effect of Ge Ratio on Thermal Stability

In this paper, novel Ni germanosilicide technology using NiPt alloy and Co overlayer has been proposed. Using the Co overlayer after NiPt deposition on Si 1-x Ge x , the formation temperature of low resistive Ni germanosilicide is lowered with high thermal stability. The thermal stability of Ni germanosilicide with different Ge fraction in is also characterized. The sheet resistance degrades as increasing the Ge fraction (x) in Si 1-x Ge x when NiPt/TiN is used. However, using the Co overlayer, the sheet resistance property among Ni germanosilicide formed with different Ge fraction is improved greatly compared with those of NiPt/TiN case (without Co overlayer). Therefore, low-temperature formation of highly thermal robust Ni germanosilicide can be achieved through the NiPt/Co/TiN tri-layer.