Embodiments of the invention described herein generally provide methods for forming cobalt silicide layers and metallic cobalt layers by using various deposition processes and annealing processes. In one embodiment, a method for forming a metallic silicide containing material on a substrate is provided which includes forming a metallic silicide material over or on a silicon-containing surface during a vapor deposition process by sequentially depositing a plurality of metallic silicide layers and silyl layers on the substrate, depositing a metallic capping layer over or on the metallic silicide material, heating the substrate during an annealing process, and depositing a metallic contact material over or on the barrier material. In one example, the metallic silicide layers and the metallic capping layer both contain cobalt. The cobalt silicide material may contain a silicon/cobalt atomic ratio of about 1.9 or greater, such as greater than about 2.0, or about 2.2 or greater.