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.

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.

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.

Provided are high purity tungsten pentachloride, and a method for obtaining such high purity tungsten pentachloride at a high yield and in an efficient manner. Tungsten pentachloride in which a total content of metal impurities excluding Sb, Ti, and As is less than 10 wtppm is obtained by uniformly mixing one or more types of reducing agents selected from Sb, Ti, and As and tungsten hexachloride at a molar ratio of 1.0:2.0 to 1.0:5.0 (reducing agent/WCl.sub.6 ratio) in an inert atmosphere to obtain a mixture, heating and reducing the mixture for 1 to 100 hours in a temperature range in which a chloride of tungsten and the reducing agent becomes a liquid phase to obtain a reduced product, heating the reduced product for 1 to 100 hours at 100 Pa or less and in a temperature range of 90 to 130° C., and performing reduced-pressure distillation thereto to obtain a reduced-pressure distilled product, heating and sublimating the reduced-pressure distilled product for 1 to 100 hours at 100 Pa or less and in a temperature range of 130 to 170° C., and performing sublimation purification of achieving precipitation at 70 to 120° C.

Provided are high purity tungsten pentachloride, and a method for obtaining such high purity tungsten pentachloride at a high yield and in an efficient manner. Tungsten pentachloride in which a total content of metal impurities excluding Sb, Ti, and As is less than 10 wtppm is obtained by uniformly mixing one or more types of reducing agents selected from Sb, Ti, and As and tungsten hexachloride at a molar ratio of 1.0:2.0 to 1.0:5.0 (reducing agent/WCl.sub.6 ratio) in an inert atmosphere to obtain a mixture, heating and reducing the mixture for 1 to 100 hours in a temperature range in which a chloride of tungsten and the reducing agent becomes a liquid phase to obtain a reduced product, heating the reduced product for 1 to 100 hours at 100 Pa or less and in a temperature range of 90 to 130° C., and performing reduced-pressure distillation thereto to obtain a reduced-pressure distilled product, heating and sublimating the reduced-pressure distilled product for 1 to 100 hours at 100 Pa or less and in a temperature range of 130 to 170° C., and performing sublimation purification of achieving precipitation at 70 to 120° C.

A treatment method according to the present invention includes bringing a metal oxyfluoride of the general formula: MO.sub.(6-x)/2F.sub.x (where 0<x<6; and M=W or Mo) into contact with a fluorine-containing gas at a reaction temperature higher than or equal to 0° C. and lower than 400° C., thereby converting the metal oxyfluoride to a metal hexafluoride of the general formula: MF.sub.6 (where M=W or Mo). This treatment method enables conversion of the metal oxyfluoride to the high vapor pressure compound without the use of a plasma generator and can be applied to cleaning of a metal fluoride production apparatus or cleaning of a film forming apparatus.

A treatment method according to the present invention includes bringing a metal oxyfluoride of the general formula: MO.sub.(6-x)/2F.sub.x (where 0<x<6; and M=W or Mo) into contact with a fluorine-containing gas at a reaction temperature higher than or equal to 0° C. and lower than 400° C., thereby converting the metal oxyfluoride to a metal hexafluoride of the general formula: MF.sub.6 (where M=W or Mo). This treatment method enables conversion of the metal oxyfluoride to the high vapor pressure compound without the use of a plasma generator and can be applied to cleaning of a metal fluoride production apparatus or cleaning of a film forming apparatus.

A tungsten hexafluoride manufacturing method of the present invention includes a reaction step of reacting tungsten containing arsenic or an arsenic compound with a gas of a fluorine element-containing compound so as to obtain a mixture containing tungsten hexafluoride and a trivalent arsenic compound, and a distillation step of distilling and purifying the mixture so as to separate and remove a fraction containing the trivalent arsenic compound and to obtain tungsten hexafluoride.

A tungsten hexafluoride manufacturing method of the present invention includes a reaction step of reacting tungsten containing arsenic or an arsenic compound with a gas of a fluorine element-containing compound so as to obtain a mixture containing tungsten hexafluoride and a trivalent arsenic compound, and a distillation step of distilling and purifying the mixture so as to separate and remove a fraction containing the trivalent arsenic compound and to obtain tungsten hexafluoride.