The term salicide refers to a technology used in the microelectronics industry used to form electrical contacts between the semiconductor device and the supporting interconnect structure. The salicide process involves the reaction of a thin metal film with silicon in the active regions of the device, ultimately forming a metal silicide contact through a series of annealing and/or etch processes. The term "salicide" is a compaction of the phrase self-aligned silicide. The description "self-aligned" suggests that the contact formation does not require lithographic patterning processes, as opposed to a non-aligned technology such as polycide. The term salicide is also used to refer to the metal silicide formed by the contact formation process, such as "titanium salicide", although this usage is inconsistent with accepted naming conventions in chemistry.
Polycide is a silicide formed over polysilicon. Widely used in DRAMs. In a polycide MOSFET transistor process, the silicide is formed only over the polysilicon film as formation occurs prior to any polysilicon etch. Polycide processes contrast with salicide processes in which silicide is formed after the polysilicon etch. Thus, with a salicide process, silicide is formed over both the polysilicon gate and the exposed monocrystalline terminal regions of the transistor in a self-aligned fashion.