CoSi2s

CoSi2, or cobalt disilicide, is a binary inorganic compound with the formula CoSi2. It is a silicide formed from cobalt and silicon and is one of the cobalt silicide phases studied for microelectronic applications. CoSi2 is commonly produced by silicidation, where a cobalt layer deposited on silicon is annealed at elevated temperature. During this process cobalt diffuses into the silicon and a crystalline CoSi2 layer forms, often with good step coverage and, on appropriate silicon substrates, favorable epitaxial alignment.

In terms of properties, CoSi2 is metallic and exhibits high electrical conductivity, along with notable thermal stability. It forms a stable interface with silicon and is relatively resistant to oxidation under device operating conditions. These characteristics, together with its compatibility with silicon, make CoSi2 a useful material for forming low-resistance contacts in silicon-based integrated circuits.

Historically, cobalt disilicide gained prominence as a practical silicide for source/drain and gate contacts because it can reduce contact resistance compared with pure metal contacts and can be integrated using existing silicon processing steps. While its use has evolved with advances in device architectures and alternative silicides, CoSi2 remains a benchmark system for silicidation processes and continues to be cited in studies of metal-silicon interactions and microfabrication.

See also: silicides, cobalt silicides, silicidation, semiconductor contacts.