A process of conditioning tungsten pentachloride to form specific crystalline phases are disclosed. The specific crystalline phases permit stable vapor pressures over extended periods of time during vapor deposition and etching processes.

A process of conditioning tungsten pentachloride to form specific crystalline phases are disclosed. The specific crystalline phases permit stable vapor pressures over extended periods of time during vapor deposition and etching processes.

Condensable metal halide materials, such as but not limited to tungsten chloride (WCl.sub.6), can be used to deposit metal films or metal containing films in a chemical vapor deposition (CVD) or atomic layer deposition process. Described herein are high purity compositions comprising condensable materials and methods to purify condensable materials. In one aspect, there is provided a composition comprising: tungsten hexachloride which is substantially free of at least one impurity and wherein the tungsten hexachloride comprises at least 90%, preferably 95% and more preferably 99% by weight or greater of a -WCl.sub.6 and 5% by weight or less of the -WCl.sub.6 as measured by X-ray diffraction.

Condensable metal halide materials, such as but not limited to tungsten chloride (WCl.sub.6), can be used to deposit metal films or metal containing films in a chemical vapor deposition (CVD) or atomic layer deposition process. Described herein are high purity compositions comprising condensable materials and methods to purify condensable materials. In one aspect, there is provided a composition comprising: tungsten hexachloride which is substantially free of at least one impurity and wherein the tungsten hexachloride comprises at least 90%, preferably 95% and more preferably 99% by weight or greater of a -WCl.sub.6 and 5% by weight or less of the -WCl.sub.6 as measured by X-ray diffraction.

A production method of tungsten hexafluoride according to one embodiment of the present invention includes: a first step of bringing tungsten having an oxide film into contact with a fluorine gas or inert gas containing 50 vol ppm to 50 vol % of hydrogen fluoride in a reactor, thereby removing the oxide film from the tungsten; and a second step of bringing the tungsten from which the oxide film has been removed by the first step into contact with a fluorine-containing gas to form tungsten hexafluoride.

A production method of tungsten hexafluoride according to one embodiment of the present invention includes: a first step of bringing tungsten having an oxide film into contact with a fluorine gas or inert gas containing 50 vol ppm to 50 vol % of hydrogen fluoride in a reactor, thereby removing the oxide film from the tungsten; and a second step of bringing the tungsten from which the oxide film has been removed by the first step into contact with a fluorine-containing gas to form tungsten hexafluoride.

A visible-light-responsive photocatalyst powder includes a tungsten oxide powder. The tungsten oxide powder has color whose a* is 5 or less, b* is 5 or more, and L* is 50 or more when the color of the powder is expressed by an L*a*b* color system. Further, the tungsten oxide powder has a BET specific surface area in a range of 11 to 820 m.sup.2/g.

A visible-light-responsive photocatalyst powder includes a tungsten oxide powder. The tungsten oxide powder has color whose a* is 5 or less, b* is 5 or more, and L* is 50 or more when the color of the powder is expressed by an L*a*b* color system. Further, the tungsten oxide powder has a BET specific surface area in a range of 11 to 820 m.sup.2/g.

A molybdenum oxychloride or a tungsten oxychloride, wherein the molybdenum oxychloride or the tungsten oxychloride has a moisture content of less than 1 wt %. A method of producing a molybdenum oxychloride or a tungsten oxychloride, wherein a molybdenum oxide or a tungsten oxide as a raw material is subject to dehydration treatment at 400 C. or higher and 800 C. or less, and the raw material that underwent dehydration treatment is thereafter reacted with a chlorine gas to synthesize a molybdenum oxychloride or a tungsten oxychloride. A molybdenum oxychloride or a tungsten oxychloride is thereby provided having a low moisture content, and a production method thereof is provided.

A tungsten hexafluoride manufacturing method of the present invention includes a reaction step of reacting tungsten with a gas of a fluorine element-containing compound so as to obtain a mixture that contains tungsten hexafluoride and hydrogen fluoride-containing impurities, and a discharge step of performing distillation of the mixture while performing a discharge operation at least two or more times during the distillation so as to obtain tungsten hexafluoride, the discharge operation being an operation in which a storage operation and a purge operation are alternately performed.