NF3 treating process

Abstract

A process for treating NF 3 useful as a dry etching gas and cleaning gas in processes for producing LSI, TFT, and solar cell and in an electron photographic processes. The treating process comprises following step: (a) preparing a reactor including agitator blades for agitating gas in the reactor and generating a flow of the gas, and a gas flow guide tube for efficiently circulating and dispersing the gas flow generated by the agitator blades in a space of the reactor; (b) stationarily placing at least one substance selected from the group consisting of a metal and a metal compound within a reactor, the metal being at least one metal selected from the group consisting of Si, B, W, Mo, V, Se, Te and Ge, the metal compound being at least one metal compound selected from the group consisting of solid compounds of Si, B, W, Mo, V, Se, Te and Ge; (c) introducing a gas containing NF 3 into the reactor to react the introduced gas with at least one substance of the metal and the metal compound at a temperature ranging from 400 to 900° C. upon operating the agitator blades of the reactor so as to form a fluoride gas; and (d) capturing the fluoride gas.

What is claimed is:  
     
         1 . A process for treating NF 3 , comprising the following steps: 
 preparing a first reactor including agitator blades for agitating gas in the first reactor and generating a flow of the gas, and a gas flow guide tube for efficiently circulating and dispersing the gas flow generated by the agitator blades in a space of the first reactor;    stationarily placing at least one substance selected from the group consisting of a metal and a metal compound within a first reactor, the metal being at least one metal selected from the group consisting of Si, B, W, Mo, V, Se, Te and Ge, the metal compound being at least one metal compound selected from the group consisting of solid compounds of Si, B, W, Mo, V, Se, Te and Ge;    introducing a gas containing NF 3  into the first reactor to react the introduced gas with at least one substance of the metal and the metal compound at a temperature ranging from 400 to 900° C. upon operating the agitator blades of the first reactor so as to form a fluoride gas; and    capturing the fluoride gas.    
     
     
         2 . A process as claimed in  claim 1 , wherein the preparing step includes preparing the first reactor including an outer tube in which the gas flow guide tube is generally coaxially located so as to form an outer cylindrical space between the outer tube and the gas flow guide tube, and a tray on which the at least one substance of the metal and the metal compound is placed, the tray being located inside the gas flow guide tube, and locating the agitator blades inside the outer tube and at a side upstream of the tray.  
     
     
         3 . A process as claimed in  claim 1 , further comprising the step of causing the gas within the gas flow guide tube to flow at a mean flow rate of 0.5 m/sec or more so as to be circulated and dispersed.  
     
     
         4 . A process as claimed in  claim 1 , further comprising the following steps: 
 connecting a second reactor in series with and at a side downstream of the first reactor, the second reactor having a fixed bed including at least one substance selected from the group consisting of a metal and a metal compound within a first reactor, the metal being at least one metal selected from the group consisting of Si, B, W, Mo, V, Se, Te and Ge, the metal compound being at least one metal compound selected from the group consisting of solid compounds of Si, B, W, Mo, V, Se, Te and Ge; and    introducing gas discharged from the first reactor to the second reactor so as to react the gas with the at least one substance of the metal and the metal compound within a temperature ranging from 400 to 900° C.    
     
     
         5 . A system for treating NF 3 , comprising: 
 a reactor including    an outer tube into which a gas containing NF 3  is supplied,    agitator blades disposed inside said outer tube for agitating the gas and generating a flow of the gas,    a gas flow guide tube disposed inside said outer tube to efficiently circulate or disperse the gas flow generated by the agitator blades in a space of the outer tube,    at least one substance selected from the group consisting of a metal and a metal compound, disposed inside said gas flow guide tube, said metal being at least one metal selected from the group consisting of Si, B, W, Mo, V, Se, Te and Ge, said metal compound being at least one metal compound selected from the group consisting of solid compounds of Si, B, W, Mo, V, Se, Te and Ge, and    a first heater disposed outside said outer tube to heat the space inside the outer tube at a temperature ranging from 400 to 900° C.    
     
     
         6 . A system as claimed in  claim 5 , wherein the gas flow guide tube of said reactor is generally coaxially located inside said outer tube so as to form an outer cylindrical space between the outer tube and the gas flow guide tube, wherein said reactor includes a tray on which the at least one substance of the metal and the metal compound is placed, the tray being located inside the gas flow guide tube; wherein the agitator blades of said reactor is located inside the outer tube and at a side upstream of the tray so as to cause the gas to recirculate through a space formed inside said gas flow guide tube and through said outer cylindrical space.  
     
     
         7 . A system as claimed in  claim 1 , wherein said agitator blades are arranged to cause the gas within the gas flow guide tube to flow at a mean flow rate of 0.5 m/sec or more.