Preparation
(1) Mix tungsten powder and silicon powder in a molar ratio of 1:2, and titanium powder and graphite powder in a molar ratio of 1:1, and then mix them evenly. (2) Place the W-Si mixed powder in the center of the crucible, and evenly place the Ti-C mixed powder between the W-Si mixed powder and the crucible. Finally, place a layer of Ti-C mixed powder on top of all the mixed powders. The weight ratio of Ti-C mixed powder to W-Si mixed powder in the crucible is (0.8~1.2):1. (3) Place the crucible containing the mixed powder into a sealed reactor, evacuate it, and then fill it with argon gas. Then, use a tungsten wire to energize the mixture to initiate the reaction between the materials. (4) After cooling, remove the reacted material, separate the titanium carbide and TUNGSTEN SILICIDE, and crush them separately to obtain titanium carbide and TUNGSTEN SILICIDE powders.
Description
Tungsten silicide (WSi2) is an inorganic compound, a silicide of tungsten. It is an electrically conductive ceramic
material. Tungsten silicide can react violently with substances such as strong acids, fluorine, oxidizers, and interhalogens.
It is employed in microelectronics as a contact material, with a resistivity of 60-80 μΩ cm; it forms at 1000℃. It is frequently used as a shunt over polysilicon lines to increase their conductivity and increase signal speed.
Chemical Properties
Blue-gray, very hard solid. Insoluble in water; attacked by fused
alkalies and mixture of nitric and hydrofluoric acids.
Uses
Oxidation-resistant coatings, electrical resistance
and refractory applications.
Uses
Tungsten silicide is used in microelectronics as a contact material. It is also used as a shunt over polysilicon lines to increase their conductivity and increase signal speed. Further, it acts as a barrier layer between silicon and other metals. In addition to this, it is used in microelectro mechanical systems and for oxidation-resistant coatings. It is also employed as a replacement for earlier tungsten films.
