7783-82-6

Usage

Uses

1. Used in the Electronics Industry:
Tungsten hexafluoride is used as a source of tungsten metal for connecting the aluminum layers within semiconductor devices. Its application in this industry is due to its ability to provide a reliable and efficient connection between the layers, enhancing the performance of the semiconductor devices.
2. Used in the Chemical Industry:
Tungsten hexafluoride is employed in the manufacture of other chemicals, where its unique properties and reactivity contribute to the synthesis of various compounds. Its use in this industry is attributed to its versatility and ability to participate in different chemical reactions, leading to the production of a wide range of chemicals.

Physical and Chemical Properties

Chemical formula is WF6. The molecular weight is 297.84. It is colorless gas or light yellow liquid. It has strong irritant. It is poisonous, its toxicity is similar with fluorine. When the temperature is very low, it is white solid. It is soluble in organic solvents and then generate a special color. When meet water, it can decompose. In the air, it can decompose with strong smoke by moisture, and generate yellow tungstate or tungsten trioxide. Chemical properties is lively. And almost all metals (except gold and platinum) can react with it. It is also corrosive for nickel, monel and stainless steel, but Ni and stainless steel have resistance for corrosion. When dry, it is less corrosive to glass, while in moisture, it is able to react quickly. It can react strong with gaseous ammonia. Ammonia or an alkali can absorb it . It can generate double salt with alkali metal fluoride. It is soluble in benzene and other organic solvents. [Density] 3.44×103kg/m3 (15℃, liquid) [Melting point] 2.5℃ (5.6 × 104 Pa) [Boiling point] 17.5℃ [Critical temperature] 171℃ [Critical pressure] 445.8kPa [Preparation method] Metal tungsten powder and elemental fluorine can react to synthesize it directly. [Application] (1) It is strong fluorinating agent, it can synthesize tungsten film in vapor deposition method. (2) it is used in the microelectronics industry for chemical vapor deposited tungsten silicide or tungsten, to produce a low resistance, a high melting point interconnects. Figure 1 shows the molecular structure of tungsten hexafluoride.

Hazardous characteristics

When meet moisture, air or water, it will decompose and emit toxic and corrosive hydrogen fluoride fumes. It can cause very serious burns for skin, eyes, mucous membranes. When high concentrations expose, it can cause nausea, vomiting, abdominal pain, convulsions, kidney damage. The above information is edited by the lookchem of Wang Xiaodong.

Storage Instructions

It shoud be packed in special cylinders and stored in a cool, ventilated coffers. Avoid direct sunlight. Keep away from heat and sources of ignition. Prevent moisture. Metal, glass should be isolated storage. "poison gas" signs should be affixed. Aviation, railway transportation is prohibited. When other combustibles on fire around, dry powder, carbon dioxide can be used to extinguish. Water can be used to cool cylinder, and then close the valve quickly.

First-aid steps

It has eye irritation and can lead to blind, eyes should continue to be rinsed, go to the hospital fast for treatment. After corrosion, skin and mucous membranes is difficult to heal, it should be washed with water, and then coated with magnesium oxide ointment or glycerol dilute ammonia, and seek medical advice.

Flammability hazard characteristics

When meet water, it can decompose into toxic hydrogen fluoride gas and tungstate.

Extinguishing agent

Water.

Occupational standards

TLV-TWA 5 mg (tungsten)/cubic meter; STEL 10 mg (tungsten)/cubic meter.

Air & Water Reactions

Decomposes in water giving hydrofluoric acid, another corrosive material.

Reactivity Profile

Tungsten hexafluoride emits very toxic and irritating fumes containing metallic tungsten and tungsten fluorides when heated to decomposition. Reacts violently with tetramethoxysilane [Jacob, E., Angew. Chem., 1982, 21, p. 143].

Safety Profile

A poison and corrosive liquid or gas.

Potential Exposure

A strong halogenating agent. Used to apply tungsten coatings to other surfaces by vapor deposition process; making electronics and components; in the manufacture of other chemicals.

Shipping

UN2196 Tungsten hexafluoride, Hazard Class: 2.3; Labels: 2.3-Poisonous gas, 8-Corrosive material, Inhalation Hazard Zone B. Cylinders must be transported in a secure upright position, in a well-ventilated truck. Protect cylinder and labels from physical damage. The owner of the compressed gas cylinder is the only entity allowed by federal law (49CFR) to transport and refill them. It is a violation of transportation regulations to refill compressed gas cylinders without the express written permission of the owner.

Incompatibilities

Decomposes on contact with water and moist air, forming highly corrosive hydrofluoric acid. Violent reaction on contact with methyl silicate.

InChI:InChI=1/6FH.W/h6*1H;/q;;;;;;+6/p-6/rF6W/c1-7(2,3,4,5)6

Upstream product

• 13709-36-9 xenon difluoride 
• 14040-11-0 tungsten hexacarbonyl 
• 7440-33-7 tungsten 
• 16921-96-3 iodine heptafluoride 
• 7782-41-4 fluorine 
• 7783-70-2 antimony pentafluoride 
• 13283-01-7 tungsten(VI) chloride 
• 7783-41-7 difluoroether 
• 7664-39-3 hydrogen fluoride 
• 14521-18-7 ruthenium(V) fluoride 
• 7790-89-8 chlorine monofluoride 
• 7784-35-2 arsenic(III) fluoride 
• 13773-81-4 krypton difluoride 
• 13520-79-1 tungsten oxide tetrafluoride 

Downstream Products

• 7782-41-4 fluorine 
• 593-53-3 Methyl fluoride 
• 7637-07-2 boron trifluoride 
• 22441-22-1 tungsten(VI) pentafluoride methoxide 
• 7440-33-7 tungsten 
• 7664-39-3 hydrogen fluoride 
• 7783-77-9 molybdenum(VI) fluoride 
• 13819-84-6 molybdenum(V) fluoride 
• 19357-83-6 tungsten pentafluoride 
• 11128-24-8 silicon monofluoride 
• 13966-66-0 difluorosilylene 
• 14835-14-4 trifluorosilyl radical 
• 7783-61-1 silicon tetrafluoride 
• 53653-01-3 F₇W^(1-) 

Relevant academic research and scientific papers

Kinetics of interaction of tungsten metal with a fluoropolymer

The kinetics of the interaction of tungsten metal with a copolymer of tetrafluoroethylene and vinylidene difluoride (TFE-VDF) has been studied by mass spectrometry (MS), thermogravimetry (TG), and differential scanning calorimetry (DSC). Measurements were

Intercalation of WF6 in the interlayer space of multiwall carbon nanotubes - Structural and morphological aspects

The reactivity of multiwall carbon nanotubes toward WF6, a strong Lewis acid, has been studied. A material of nominal composition C 36WF6 has been obtained and characterized by X-ray diffraction. Intercalation between pseudo-graphitic layers has been evidenced, leading to a staging phenomenon at the nanometer scale. A structural model is proposed and the intercalation chemistry of multiwalled carbon nanotubes is discussed.

Development and implementation of industrial technologies for synthesis of fluorine compound with the application of elemental fluorine

A survey is given on the application of elemental fluorine in chemical plants and research centers of Russian Federation.

Chemical interaction of fluoropolymers with transition metals

Chemical interaction of transition metals (Mo, W, Ta, Nb, and Ti) with a tetrafluoroethylene-vinylidene fluoride (TFE-VDF) copolymer (21 mol % TFE + 79 mol % VDF) has been studied by differential scanning calorimetry (DSC) and mass spectrometry. The DSC c

Reactions of Ruthenium Pentafluoride with Refractory Metals

Differential thermal analysis, X-ray powder diffraction, and IR spectroscopy were the tools used to study reactions of powdered and compact samples of V, Nb, Mo, and W, as well as of Si and Ge, with RuF5. The onset temperatures and products of the reactions were determined. The possibility of using exchange reactions to apply ruthenium coatings to the simple substances that form volatile higher fluorides was shown.

Thermodynamic properties of tungsten ditelluride (WTe2). II. Standard molar enthalpy of formation at the temperature 298.15 K

The standard molar enthalpies of formation of WTe2(cr) and TeF6(g) have been determined by combustion calorimetry in high-pressure fluorine: ΔfHmo(WTe2, cr, 298.15K) = -(38+/-5)kJmol-1, and ΔfHsub

Standard molar enthalpy of formation at 298.15 K of the β-modification of molybdenum ditelluride

Fluorine-combustion calorimetry of a high-purity sample of molybdenum ditelluride has yielded the standard molar enthalpy of formation: ΔfH0m(MoTe2, cr, β, 298.15 K) = -(84.2 +/- 4.6) kJ * mol-1.At 298.15 K, the enthalpy of the hypothetical β-to-α transition in MoTe2 is approximately -6 kJ * mol-1.The present result for ΔfH0m(MoTe2) has been combined with literature values for the decomposition pressures of MoTe2 to yield ΔfH0m(Mo3Te4, cr, 298.15 K) = -(185 +/- 10) kJ * mol-1.Our previously published ΔfH0m(TeF6) (Trans.Faraday Soc. 1966, 62, 558) has been revised slightly to -(1371.8 +/- 1.8) kJ * mol-1.

Mechanism for selectivity loss during tungsten CVD

We have investigated possible mechanisms for the loss of selectivity (i.e., deposition on silicon dioxide) during tungsten CVD by reduction of tungsten hexafluoride and found strong evidence that selectivity loss is initiated by desorption of tungsten sub

Standard molar enthalpy of formation by fluorine-combustion calorimetry of tungsten diselenide (WSe2). Thermodynamics of the high-temperature vaporization of WSe2. Revised value of the standard molar enthalpy of formation of molybdenite (MoS2)

A high-purity sample of WSe2, containing in total mass fraction less than 1 x 10-4 of oxygen and other impurities, has been synthesized by combination of the elements.The standard specific energy of combustion of pure WSe2 in fluorine, as measured by high-precision calorimetry, is -(10993.7+/-15.0) J*g-1, and the derived standard molar enthalpy of formation ΔfHm0 is -(185.3+/-5.5) kJ*mol-1 at T = 298.15 K and p0 = 0.101325 MPa.This result is compared with other literature values, and the equilibrium partial pressures of Se2(g) and Se(g) are estimated for decomposition of WSe2 to and 1/2WSe2 to .Our published result (J.Chem.Thermodynamics 1970, 2, 797) for ΔfHm0(MoS2) at 298.15 K has been revised to -(271.8+/-4.9) kJ*mol-1.

Preparation and study by raman spectroscopy of KrF2·MOF4, XeF2·MOF4, and XeF2·2MOF4 (M = Mo, W) and a solution 19F NMR study of KrF2·nMoOF4 (n = 1-3) and KrF2·WOF4

The first krypton difluoride-metal oxide fluoride adducts have been prepared by reaction of KrF2 with MOF4 (M = Mo, W) in SO2ClF solution at low temperatures. The 19F NMR spectra of KrF2·nMoOF4 (n = 1-3) and KrF2·WOF4 in solution show that they are best formulated as essentially covalent structures containing Kr?F?M bridges and mononuclear or polynuclear metal oxide fluoride moieties. Studies of equilibria involving Kr-O-W- and Kr?F?W-bridged species have been interpreted to suggest that stable krypton-oxygen bonds are unlikely. Raman spectra of the solid KrF2·MOF4 (M = Mo, W) adducts have been compared with those of the analogous xenon compounds and all have been interpreted in terms of covalent fluorine-bridged structures. The Raman spectra of the solid adducts XeF2·2MOF4 are also reported.