Tungsten disilicide

Tungsten disilicide

Names
IUPAC name Tungsten disilicide
Identifiers
CAS Number	12039-88-2 Y
Jmol 3D model	Interactive image
PubChem	16212546
InChI InChI=1S/2Si.W
SMILES [Si]#[W]#[Si]
Properties
Chemical formula	WSi2
Molar mass	240.011 g/mol
Appearance	blue-gray tetragonal crystals
Density	9.3 g/cm3
Melting point	2,160 °C (3,920 °F; 2,430 K)
Solubility in water	insoluble
Vapor pressure	{{{value}}}
Related compounds
Other anions	Tungsten carbide Tungsten nitride
Other cations	Molybdenum disilicide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YN ?)
Infobox references

Tungsten silicide (WSi₂) is an inorganic compound, a silicide of tungsten. It is an electrically conductive ceramic material.

Chemistry

Tungsten silicide can react violently with substances such as strong acids, fluorine, oxidizers, and interhalogens.

Applications

It is used in microelectronics as a contact material, with resistivity 60–80 μΩ cm; it forms at 1000 °C. It is often used as a shunt over polysilicon lines to increase their conductivity and increase signal speed. Tungsten silicide layers can be prepared by chemical vapor deposition, e.g. using monosilane or dichlorosilane with tungsten hexafluoride as source gases. The deposited film is non-stoichiometric, and requires annealing to convert to more conductive stoichiometric form. Tungsten silicide is a replacement for earlier tungsten films. Tungsten silicide is also used as a barrier layer between silicon and other metals, e.g. tungsten.

Tungsten silicide also finds use in microelectromechanical systems and for oxidation-resistant coatings.

Films of tungsten silicide can be plasma-etched using e.g. nitrogen trifluoride gas.