Wet-oxidation apparatus and wet-oxidation method

Abstract

A wet-oxidation apparatus comprises a reaction tube capable of accommodating a semiconductor wafer; a water vapor generating apparatus for generating water vapor; a gas supply passage for supplying gas into the reaction tube; a discharge passage; an inert gas supply unit for supplying an inert gas; a gas switching unit capable of switching between the water vapor from the water vapor generating unit and the inert gas from the inert gas supply unit, so as to supply either one of the water vapor and the inert gas to the gas supply passage; and a control unit controlling such that: at least while wet-oxidation processing of the semiconductor wafer are conducted predetermined times in the reaction tube, the water vapor generating apparatus continuously generates the water vapor; whenever the wet-oxidation processing is started one time, the water vapor from the water vapor generating apparatus is switched toward the gas supply passage; and whenever the wet-oxidation processing is completed one time, the water vapor from the water vapor generating apparatus is switched toward the discharge passage, and the inert gas from the inert gas supply unit is supplied to the gas supply passage.

What is claimed is:  
     
         1 . A wet-oxidation apparatus, comprising: 
 a reaction tube capable of accommodating a semiconductor wafer or semiconductor wafers;    a water vapor generating apparatus for generating water vapor;    a gas supply passage for supplying gas into said reaction tube;    a discharge passage; and    a gas switching unit capable of switching the water vapor from said water vapor generating apparatus into either one of said gas supply passage and said discharge passage.    
     
     
         2 . A wet-oxidation apparatus as recited in    claim 1   , further comprising an inert gas supply unit for supplying an inert gas, 
 wherein said gas switching unit switches between the water vapor from said water vapor generating unit and the inert gas from said inert gas supply unit, so as to supply either one of said water vapor and said inert gas to said gas supply passage.    
     
     
         3 . A wet-oxidation apparatus as recited in    claim 2   , wherein 
 when wet-oxidation of said semiconductor wafer or wafers is conducted, a supply of the inert gas from said inert gas supply unit to said gas supply passage is stopped, and the water vapor from said water vapor generating unit is supplied to said gas supply passage, and    when the wet-oxidation of said semiconductor wafer or wafers is not conducted, the water vapor from said water vapor generating unit is not supplied to said gas supply passage and is discharged by said discharge passage, and the inert gas from said inert gas supply unit is supplied to said gas supply passage.    
     
     
         4 . A wet-oxidation apparatus as recited in    claim 1   , further comprising a control unit capable of controlling said water vapor generating apparatus and said gas switching unit, wherein 
 said control unit controls such that: 
 at least while wet-oxidation processing of said semiconductor wafer or wafers are conducted predetermined times in said reaction tube, said water vapor generating apparatus continuously generates the water vapor;  
 whenever said wet-oxidation processing is started one time, the water vapor from said water vapor generating apparatus is switched toward said gas supply passage; and  
 whenever said wet-oxidation processing is completed one time, the water vapor from said water vapor generating apparatus is switched toward said discharge passage.  
   
     
     
         5 . A wet-oxidation apparatus as recited in    claim 4   , further comprising an inert gas supply unit for supplying an inert gas, 
 wherein said gas switching unit switches between the water vapor from said water vapor generating unit and the inert gas from said inert gas supply unit, so as to supply either one of said water vapor and said inert gas to said gas supply passage, and    wherein said control unit controls such that: 
 at least while the wet-oxidation processing of said semiconductor wafer or wafers are conducted predetermined times in said reaction tube, said the water vapor generating apparatus continuously generates the water vapor;  
 whenever said wet-oxidation processing is started one time, the water vapor from said water vapor generating apparatus is switched toward said gas supply passage; and  
 whenever said wet-oxidation processing is completed one time, the water vapor from said water vapor generating apparatus is switched toward said discharge passage, and the inert gas from said inert gas supply unit is supplied to said gas supply passage.  
   
     
     
         6 . A wet-oxidation apparatus, comprising: 
 a reaction tube capable of accommodating a semiconductor wafer or semiconductor wafers;    a water vapor generating apparatus for generating water vapor;    an inert gas supply unit for supplying an inert gas;    a gas supply passage for supplying gas into said reaction tube;    a gas switching unit capable of switching between the water vapor from said water vapor generating unit and the inert gas from said inert gas supply unit so as to supply either one of said water vapor and said inert gas to said gas supply passage.    
     
     
         7 . A wet-oxidation apparatus as recited in    claim 6   , further comprising a control unit capable of controlling said water vapor generating apparatus and said gas switching unit, wherein 
 said control unit controls such that: 
 at least while wet-oxidation processing of said semiconductor wafer or wafers are conducted predetermined times in said reaction tube, said water vapor generating apparatus continuously generates the water vapor;  
 whenever said wet-oxidation processing is started one time, the water vapor from said water vapor generating apparatus is switched toward said gas supply passage; and  
 whenever said wet-oxidation processing is completed one time, the water vapor from said water vapor generating apparatus is switched to the inert gas from said inert gas supply unit so as to supply the inert gas to said gas supply passage.  
   
     
     
         8 . A wet-oxidation apparatus, comprising: 
 a reaction tube capable of accommodating a semiconductor wafer or semiconductor wafers;    a water vapor generating apparatus for generating water vapor; and    a control unit controlling such that: 
 at least while wet-oxidation processing of said semiconductor wafer or wafers are conducted predetermined times in said reaction tube, said water vapor generating apparatus continuously generates water vapor;  
 whenever said wet-oxidation processing is started one time, the water vapor from said water vapor generating apparatus is supplied to said gas supply passage; and  
 whenever said wet-oxidation processing is completed one time, a supply of the water vapor from said water vapor generating apparatus into said reaction tube is stopped.  
   
     
     
         9 . A wet-oxidation apparatus as recited in    claim 4   , wherein said control unit controls such that the water vapor is previously generated by said water vapor generating apparatus, and after a condition of the water vapor is stabilized, the wet-oxidation processing is conducted the predetermined times.  
     
     
         10 . A wet-oxidation apparatus as recited in    claim 7   , wherein said control unit controls such that the water vapor is previously generated by said water vapor generating apparatus, and after a condition of the water vapor is stabilized, the wet-oxidation processing is conducted the predetermined times.  
     
     
         11 . A wet-oxidation apparatus as recited in    claim 8   , wherein said control unit controls such that the water vapor is previously generated by said water vapor generating apparatus, and after a condition of the water vapor is stabilized, the wet-oxidation processing is conducted the predetermined times.  
     
     
         12 . A wet-oxidation apparatus as recited in    claim 4   , wherein said wet-oxidation processing is conducted every one semiconductor wafer.  
     
     
         13 . A wet-oxidation apparatus as recited in    claim 7   , wherein said wet-oxidation processing is conducted every one semiconductor wafer.  
     
     
         14 . A wet-oxidation apparatus as recited in    claim 8   , wherein said wet-oxidation processing is conducted every one semiconductor wafer.  
     
     
         15 . A wet-oxidation apparatus as recited in    claim 4   , wherein said wet-oxidation processing is conducted every two to ten semiconductor wafers.  
     
     
         16 . A wet-oxidation apparatus as recited in    claim 7   , wherein said wet-oxidation processing is conducted every two to ten semiconductor wafers.  
     
     
         17 . A wet-oxidation apparatus as recited in    claim 8   , wherein said wet-oxidation processing is conducted every two to ten semiconductor wafers.  
     
     
         18 . A wet-oxidation apparatus as recited in    claim 1   , wherein said water vapor generating apparatus burns hydrogen to generate the water vapor.  
     
     
         19 . A wet-oxidation apparatus as recited in    claim 6   , wherein said water vapor generating apparatus burns hydrogen to generate the water vapor.  
     
     
         20 . A wet-oxidation apparatus as recited in    claim 8   , wherein said water vapor generating apparatus burns hydrogen to generate the water vapor.  
     
     
         21 . A wet-oxidation apparatus as recited in    claim 1   , wherein said gas switching unit includes a gas branching section having a branching pipe and a plurality of valves, and said wet-oxidation apparatus further includes a high-temperature keeping unit for keeping said branching pipe and said plurality of valves at a high temperature.  
     
     
         22 . A wet-oxidation apparatus as recited in    claim 6   , wherein said gas switching unit includes a gas branching section having a branching pipe and a plurality of valves, and said wet-oxidation apparatus further includes a high-temperature keeping unit for keeping said branching pipe and said plurality of valves at a high temperature.  
     
     
         23 . A wet-oxidation apparatus as recited in    claim 8   , wherein said gas switching unit includes a gas branching section having a branching pipe and a plurality of valves, and said wet-oxidation apparatus further includes a high-temperature keeping unit for keeping said branching pipe and said plurality of valves at a high temperature.  
     
     
         24 . A wet-oxidation method, wherein 
 at least while wet-oxidation processing of a semiconductor wafer or semiconductor wafers are conducted predetermined times in a reaction tube, a water vapor generating apparatus continuously generates water vapor;    whenever the wet-oxidation processing is started one time, the water vapor from said water vapor generating apparatus is supplied to said reaction tube to conduct the wet-oxidation processing of said semiconductor wafer or wafers; and    whenever said wet-oxidation processing is completed one time, the water vapor from said water vapor generating apparatus is switched toward a discharge passage.    
     
     
         25 . A wet-oxidation method as recited in    claim 24   , wherein 
 at least while the wet-oxidation processing of said semiconductor wafer or wafers are conducted the predetermined times in said reaction tube, said water vapor generating apparatus continuously generates the water vapor;    whenever said wet-oxidation processing is started one time, the water vapor from said water vapor generating apparatus is supplied to said reaction tube to conduct the wet-oxidation processing of said semiconductor wafer or wafers; and    whenever said wet-oxidation processing is completed one time, the water vapor from said water vapor generating apparatus is switched toward said discharge passage, and an inert gas from an inert gas supply unit is supplied to said reaction tube.    
     
     
         26 . A wet-oxidation method, wherein 
 at least while wet-oxidation processing of a semiconductor wafer or semiconductor wafers are conducted predetermined times in a reaction tube, a water vapor generating apparatus continuously generates water vapor;    whenever said wet-oxidation processing is started one time, the water vapor from said water vapor generating apparatus is supplied to said reaction tube to conduct the wet-oxidation processing of said semiconductor wafer or wafers; and    whenever said wet-oxidation processing is completed one time, the water vapor from said water vapor generating apparatus is switched to the inert gas from said inert gas supply unit so as to supply the inert gas to said reaction tube.    
     
     
         27 . A wet-oxidation method, wherein 
 at least while wet-oxidation processing of a semiconductor wafer or semiconductor wafers are conducted predetermined times in a reaction tube, a water vapor generating apparatus continuously generates water vapor;    whenever said wet-oxidation processing is started one time, the water vapor from said water vapor generating apparatus is supplied to said reaction tube to conduct the wet-oxidation processing of said semiconductor wafer or wafers; and    whenever said wet-oxidation processing is completed one time, a supply of the water vapor from said water vapor generating apparatus into said reaction tube is stopped.    
     
     
         28 . A wet-oxidation method as recited in    claim 27   , wherein the water vapor is previously generated by said water vapor generating apparatus, and after a condition of the water vapor is stabilized, the wet-oxidation processing is conducted the predetermined times by supplying the water vapor from said water vapor generating apparatus to said reaction tube.  
     
     
         29 . A wet-oxidation method as recited in    claim 27   , wherein said wet-oxidation processing is conducted every one semiconductor wafer.  
     
     
         30 . A wet-oxidation method as recited in    claim 27   , wherein said wet-oxidation processing is conducted every two to ten semiconductor wafers.  
     
     
         31 . A wet-oxidation method as recited in    claim 27   , wherein said water vapor generating apparatus burns hydrogen to generate water vapor.