High Purity Tungsten hexafluoride Gas (WF6) Fluorocarbon Gases

Tungsten(VI) fluoride, also known as tungsten hexafluoride, is an inorganic compound with the formula WF6. It is a toxic, corrosive, colorless gas, with a density of about 13 kg/m3 (22 lb/cu yd) (roughly 11 times heavier than air).It is the only known gaseous transition metal (or d-block) compound and the densest known gas under standard ambient temperature and pressure (298 K, 1 atm).WF6 is commonly used by the semiconductor industry to form tungsten films, through the process of chemical vapor deposition. This layer is used in a low-resistivity metallic "interconnect".It is one of seventeen known binary hexafluorides.

Tungsten metal is attractive because of its relatively high thermal and chemical stability, as well as low resistivity (5.6 μΩ·cm) and very low electromigration. WF6 is favored over related compounds, such as WCl6 or WBr6, because of its higher vapor pressure resulting in higher deposition rates.The required WF6 gas purity is rather high and varies between 99.98% and 99.9995% depending on the application.WF6 molecules have to be split up in the CVD process. The decomposition is usually facilitated by mixing WF6 with hydrogen, silane, germane, diborane, phosphine, and related hydrogen-containing gases.