Polycide is a
silicide
A silicide is a type of chemical compound that combines silicon and a (usually) more electropositive element.
Silicon is more electropositive than carbon. Silicides are structurally closer to borides than to carbides.
Similar to borides and carb ...
formed over
polysilicon
Polycrystalline silicon, or multicrystalline silicon, also called polysilicon, poly-Si, or mc-Si, is a high purity, polycrystalline form of silicon, used as a raw material by the solar photovoltaic and electronics industry.
Polysilicon is produce ...
. Widely used in
DRAMs. In a polycide
MOSFET transistor
upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink).
A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch ...
process, the silicide is formed only over the polysilicon film as formation occurs prior to any polysilicon etch. Polycide processes contrast with
salicide
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 metal th ...
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.
{{Chemistry-stub
Semiconductor device fabrication
Silicon