Topic summary
Silicon nitride
Silicon nitride is a chemical compound of the elements silicon and nitrogen. Si
3N
4 (trisilicon tetranitride) is the most thermodynamically stable and commercially important of the silicon nitrides, and the term "silicon nitride" commonly refers to this specific composition. It is a white, high-melting-point solid that is relatively chemically inert, being attacked by dilute HF and hot H
3PO
4. It is very hard (8.5 on the Mohs scale). It has a high thermal stability with strong optical nonlinearities for all-optical applications.