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

A preprocessing method comprises a sintering step of heating a solid material container filled with a solid material using a temperature which is lower than either the melting point or sublimation of the solid material, whichever is lower, and crystallizing at least part of the solid material, and an impurity removal step of heating the solid material container filled with the solid material using a temperature which is lower than either the melting point or sublimation of the solid material, whichever is lower, and removing at least part of the impurities included in the solid material.

A preprocessing method comprises a sintering step of heating a solid material container filled with a solid material using a temperature which is lower than either the melting point or sublimation of the solid material, whichever is lower, and crystallizing at least part of the solid material, and an impurity removal step of heating the solid material container filled with the solid material using a temperature which is lower than either the melting point or sublimation of the solid material, whichever is lower, and removing at least part of the impurities included in the solid material.

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 treatment method for a metal oxyfluoride 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 for a metal oxyfluoride 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 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. An object of the present invention is to provide a molybdenum oxychloride or a tungsten oxychloride having a low moisture content, as well as a production method thereof.

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.