Methods and apparatuses for high pressure gas annealing

Abstract

Novel methods and apparatuses for annealing semiconductor devices in a high pressure gas environment. According to an embodiment, the annealing vessel has a dual chamber structure, and potentially toxic, flammable, or otherwise reactive gas is confined in an inner chamber which is protected by pressures of inert gas contained in the outer chamber. The incoming gas delivery system and exhaust gas venting system are likewise protected by various methods. Embodiments of the present invention can be used, for example, for high-K gate dielectric anneal, post metallization sintering anneal, and forming gas anneal in the semiconductor manufacturing process.

1 . An apparatus, to be used in high pressure annealing, the apparatus comprising: 
 an inner chamber, said inner chamber made of non-metallic material, wherein said inner chamber is designed to maintain a first gas pressure of a first gas; and    an outer chamber, said outer chamber made of metallic material, wherein said outer chamber contains said inner chamber and is designed to maintain a second gas pressure of a second gas outside said inner chamber.    
   
   
       2 . The apparatus of  claim 1 , the apparatus further comprising: 
 a holder, said holder coupled with the said inner chamber, wherein said holder is configured to hold a semiconductor wafer inside said inner chamber.    
   
   
       3 . The apparatus of  claim 1 , the apparatus further comprising: 
 a heater, said heater coupled with at least one of said inner chamber and said outer chamber, wherein said heater is configured to heat said first gas in said inner chamber.    
   
   
       4 . The apparatus of  claim 1 , wherein: 
 said first gas pressure and said second gas pressure can be controlled separately.    
   
   
       5 . The apparatus of  claim 1 , wherein: 
 said inner chamber comprises means to open and close said inner chamber and said outer chamber comprises means to open and close said outer chamber.    
   
   
       6 . The apparatus of  claim 1 , wherein: 
 said non-metallic material comprises quartz and said metallic material comprises stainless steel.    
   
   
       7 . The apparatus of  claim 1 , further comprising: 
 means for shutting down the apparatus, wherein said means for shutting down the apparatus includes reducing at least one of said first gas pressure and said second gas pressure.    
   
   
       8 . The apparatus of  claim 1 , wherein: 
 said first gas comprises at least one of hydrogen, deuterium, fluorine, chlorine, and ammonia and said second gas comprises inert gas.    
   
   
       9 . The apparatus of  claim 1 , wherein: 
 said first gas comprises a forming gas containing deuterium, said forming gas containing 1% to 99% of deuterium.    
   
   
       10 . A method for processing an integrated circuit, the method comprising: 
 exposing the integrated circuit to an annealing atmosphere of deuterium, the annealing atmosphere having from 1% to 99% deuterium gas, and being at pressure which exceeds 25 atm.    
   
   
       11 . The method of  claim 10 , wherein: 
 the annealing atmosphere contains from 2% to 98% deuterium gas.    
   
   
       12 . A method for protecting a first pressure chamber, the first pressure chamber having first gas at first pressure, the method comprising: 
 providing a second pressure chamber, said second pressure chamber enclosing the first pressure chamber; and    adding second gas into said second pressure chamber so that the difference between the second pressure of said second gas and the first pressure of said first gas is substantially within a preset range.    
   
   
       13 . The method of  claim 12 , further comprising: 
 performing an emergency measure if the pressure difference is outside the preset range.    
   
   
       14 . The method of  claim 12 , wherein: 
 said performing comprises at least one of issuing an alarm and shutting down the apparatus.    
   
   
       15 . In a high pressure processing vessel comprising an inner chamber and an outer chamber, the outer chamber containing the inner chamber, a method for protecting the inner chamber, the inner chamber having first gas at first pressure and the outer chamber having second gas at second pressure, the method comprising: 
 adjusting at least one of the amount of the first gas in the inner chamber and the amount of the second gas in the outer chamber, so that the difference between the first pressure and the second pressure is substantially within a preset range.    
   
   
       16 . The method of  claim 15 , further comprising: 
 performing an emergency measure if the pressure difference is outside the preset range.    
   
   
       17 . The method of  claim 15 , wherein: 
 said performing comprises at least one of issuing an alarm and shutting down the high pressure processing vessel.    
   
   
       18 . A method for changing pressures in a plurality of pressure chambers, first at least one of the plurality of chambers containing first gas and second at least one of the plurality of chambers containing second gas, wherein the first at least one of the plurality of chambers is contained in the second at least one of the plurality of chambers, the method comprising: 
 changing first pressure of the first gas in the first at least one of the plurality of chambers; and    changing second pressure of the second gas in the second at least one of the plurality of chambers so that the difference between said first pressure and said second pressure remains substantially within a preset range.    
   
   
       19 . The method of  claim 18 , wherein: 
 said changing first pressure comprises at least one of    (a) adding the first gas into the first at least one of the plurality of chambers, and    (b) venting the first gas from the first at least one of the plurality of chambers.    
   
   
       20 . The method of  claim 18 , wherein: 
 said changing second pressure comprises at least one of    (a) adding the second gas into the second at least one of the plurality of chambers, and    (b) venting the second gas from the second at least one of the plurality of chambers.    
   
   
       21 . The method of  claim 18 , further comprising: 
 performing an emergency measure if the pressure difference is outside the preset range.    
   
   
       22 . An apparatus for venting gas from a high pressure annealing vessel, the vessel comprising a plurality of gas chambers, the apparatus comprising: 
 a first exhaust pipe, said first exhaust pipe configured to carry first gas from first chamber of the plurality of gas chambers;    a second exhaust pipe, said second exhaust pipe configured to carry second gas from second chamber of the plurality of gas chambers;    a third exhaust pipe; and    a compartment, said compartment coupled to said first exhaust pipe and said second exhaust pipe and said third exhaust pipe, wherein said first gas and said second gas is mixed in said compartment and the mixed gas is carried in said third exhaust pipe.    
   
   
       23 . The apparatus of  claim 22 , wherein: 
 said third exhaust pipe is configured to carry the mixed gas outside of the apparatus.    
   
   
       24 . The apparatus of  claim 22 , wherein: 
 a volume ratio between said second chamber and said first chamber is higher than a first preset value; and    a pressure ratio between said second gas in said second chamber and said first gas in said first chamber, during high pressure operation, is higher than a second preset value so that the concentration of the first gas in said mixed gas remains lower than a third preset value.    
   
   
       25 . The apparatus of  claim 22 , the apparatus further comprising: 
 a burning scrubber, said burning scrubber coupled to said third exhaust pipe; and    a fourth exhaust pipe, said fourth exhaust pipe coupled to said burning scrubber, wherein said fourth exhaust pipe is used to flow said mixed gas outside of the apparatus.    
   
   
       26 . The apparatus of  claim 22 , the apparatus further comprising: 
 a gas pipe, said gas pipe coupled to said compartment, wherein said gas pipe is configured to flow third gas into said third exhaust pipe.    
   
   
       27 . The apparatus of  claim 26 , wherein: 
 said gas pipe is configured such that the flow of said third gas in said gas pipe is adjusted according to the amount of gas flow in at least one of said first exhaust pipe and said second exhaust pipe.    
   
   
       28 . The apparatus of  claim 26 , wherein: 
 flow of said third gas in said gas pipe is maintained so that there is outward gas flow in said third exhaust pipe toward outside of the apparatus, wherein flow of air from outside of the apparatus in said third exhaust pipe is substantially reduced.    
   
   
       29 . A method for venting gas from a plurality of gas chambers, the method comprising: 
 performing venting first gas from a first chamber from the plurality of chambers; and    performing venting second gas from a second chamber from the plurality of chambers such that a ratio between the amount of the first gas vented in a given period of time and the amount of the second gas in the given period of time remains above a first preset value and below a second preset value.    
   
   
       30 . The method of  claim 29 , further comprising: 
 adding third gas during at least one of said performing venting first gas and said performing venting second gas.    
   
   
       31 . An apparatus, to be used in high pressure annealing, the apparatus comprising: 
 a first chamber, said first chamber designed to maintain a first gas pressure of a first gas;    a second chamber, said second chamber designed to maintain a second gas pressure of a second gas, wherein said second chamber is coupled to said first chamber such that said first gas is surrounded by said second gas;    a first injection pipe, said first injection pipe coupled to said first chamber, wherein said first injection pipe is configured to carry said first gas; and    a second injection pipe, said second injection pipe coupled to said second chamber, wherein said second injection pipe is configured to carry said second gas.    
   
   
       32 . The apparatus of  claim 31 , further comprising: 
 first means to open and close said first chamber; and    second means to open and close said second chamber.    
   
   
       33 . The apparatus of  claim 32 , further comprising: 
 means to flow a gas, wherein said means to flow a gas is substantially close to at least one of said first means to open and close and second means to open and close and said gas is an inert gas.    
   
   
       34 . The apparatus of  claim 31 , wherein: 
 said first injection pipe comprises a double-walled stainless steel pipe, and said second injection pipe comprises a double-walled stainless steel pipe.    
   
   
       35 . An apparatus for annealing a semiconductor device using high pressure gas, the apparatus comprising: 
 a vessel, said vessel comprising a first gas chamber and a second gas chamber, said first gas chamber configured to contain first gas and said second gas chamber configured to contain second gas, wherein said first gas chamber is enclosed in said second gas chamber;    an incoming gas flow control system, said incoming gas flow control system coupled to said vessel, and said incoming gas flow control system comprising a first gas pipe and a second gas pipe, wherein said first gas pipe is coupled to said first gas chamber and said second gas pipe is coupled to said second gas chamber; and    a gas venting system, said gas venting system coupled to said vessel.    
   
   
       36 . The apparatus of  claim 35 , wherein: 
 said incoming gas flow control system further comprises a valve for opening and closing gas flow; and    at least one of (a) said valve, (b) said first gas pipe, and (c) said second gas pipe, is protected by double wall construction.    
   
   
       37 . The apparatus of  claim 35 , wherein: 
 said incoming gas flow control system further comprises a gas control cabinet, wherein said gas control cabinet is coupled to at least one of said first gas pipe and said second gas pipe.    
   
   
       38 . The apparatus of  claim 35 , wherein: 
 said gas venting system comprises a first exhaust pipe, a second exhaust pipe, and a third exhaust pipe, said first exhaust pipe coupled to said first gas chamber and said second exhaust pipe coupled to said second gas chamber, wherein said third exhaust pipe is coupled to said first exhaust pipe and said second exhaust pipe.    
   
   
       39 . The apparatus of  claim 35 , the apparatus further comprising: 
 a holder, said holder coupled with said first gas chamber, wherein said holder is configured to hold a semiconductor wafer inside said first gas chamber.    
   
   
       40 . The apparatus of  claim 35 , the apparatus further comprising: 
 a heater, said heater coupled with at least one of said first gas chamber and said second gas chamber, wherein said heater is configured to heat said first gas in said first chamber.