US Patent 10043708 Structure and method for capping cobalt contacts

A process for forming a conductive structure includes the formation of a self-aligned silicide cap over a cobalt-based contact. The silicide cap is formed in situ by the deposition of a thin silicon layer over exposed portions of a cobalt contact, followed by heat treatment to react the deposited silicon with the cobalt and form cobalt silicide, which is an effective barrier to cobalt migration and oxidation.