Method & apparatus for monitoring plasma processing operations

Abstract

The invention generally relates to various aspects of a plasma process, and more specifically the monitoring of such plasma processes. One aspect relates in at least some manner to calibrating or initializing a plasma monitoring assembly. Another aspect relates in at least some manner to various types of evaluations which may be undertaken of a plasma process which was run, and more typically one which is currently being run, within the processing chamber. Yet another aspect associated with the present invention relates in at least some manner to the endpoint of a plasma process (e.g., plasma recipe, plasma clean, conditioning wafer operation) or discrete/discernible portion thereof (e.g., a plasma step of a multiple step plasma recipe). A final aspect associated with the present invention relates to how one or more of the above-noted aspects may be implemented into a semiconductor fabrication facility, such as the distribution of wafers to a wafer production system.

What is claimed is:  
     
         1 . A plasma monitoring system for a plasma process performed in a processing chamber and comprising a first plasma step, wherein a first endpoint of said first plasma step is when a first predetermined result of said first plasma step has been achieved, said system comprising: 
 a computer-readable storage medium comprising: 
 means for receiving data on said plasma process and including said first plasma step;  
 means for evaluating a condition of said plasma during a performance of said first plasma step and from data on said first plasma step provided to said means for receiving data, wherein said condition is a cumulative result of all parameters having an effect on said plasma in said processing chamber; and  
 means for identifying an occurrence of said first endpoint from data on said first plasma step provided to said means for receiving data.  
   
     
     
         2 . A system, as claimed in  claim 1 , wherein: 
 said plasma process is selected from the group consisting of a plasma recipe which is run on at least one product in said processing chamber, a plasma cleaning operation, a plasma conditioning operation, and a qualification wafer operation.    
     
     
         3 . A system, as claimed in  claim 1 , wherein: 
 said means for receiving data comprises means for receiving data representative of optical emissions of said plasma in said processing chamber within a first wavelength range extending from about 250 nanometers to about 1,000 nanometers, from at least at a plurality of different times during said first plasma step, and at least at every 1 nanometers throughout said first wavelength range.    
     
     
         4 . A system, as claimed in  claim 1 , further comprising: 
 means for disabling said means for identifying when said means for evaluating identifies a first condition, said first condition being that said first plasma step is proceeding other than in accordance with a first standard associated with said first plasma step.    
     
     
         5 . A system, as claimed in  claim 1 , wherein: 
 said means for identifying comprises: 
 means for receiving data representative of optical emissions of said plasma in said processing chamber at least a plurality of different times during said first plasma step;  
 means for comparing said optical emissions at each of said plurality of different times with said optical emissions from an earlier of said plurality of different times; and  
 means for determining when said optical emissions from said means for comparing are within a predetermined amount of each other and equating this with said first endpoint.  
   
     
     
         6 . A system, as claimed in  claim 5 , wherein: 
 said optical emissions from said means for obtaining have an associated pattern, wherein said means for comparing comprises means for comparing said patterns of said optical emissions from said means for comparing, and wherein said predetermined amount of said means for determining defines when said patterns of said optical emissions from said means for comparing are considered a match.    
     
     
         7 . A system, as claimed in  claim 5 , wherein: 
 said means for comparing compares said optical emissions at a first time with said optical emissions from an immediately preceding time.    
     
     
         8 . A system, as claimed in  claim 1 , wherein: 
 said means for identifying comprises: 
 means for receiving data representative of optical emissions of said plasma in said processing chamber at least a plurality of different times during said first plasma step;  
 means for comparing said optical emissions at each of said plurality of different times with at least one standard; and  
 means for determining when said optical emissions from at least one of said plurality of different times is within a predetermined amount of said at least one standard.  
   
     
     
         9 . A system, as claimed in  claim 8 , wherein: 
 said at least one standard is stored on said computer-readable storage medium.    
     
     
         10 . A system, as claimed in  claim 8 , wherein: 
 said optical emissions from each of said plurality of different times have an associated pattern, wherein said at least one standard has a standard pattern, wherein said means for comparing comprises means for comparing said pattern of said optical emissions from each of said plurality of different times with said standard pattern, and wherein said predetermined amount of said means for determining defines when said patterns from said means for comparing are considered a match.    
     
     
         11 . A system, as claimed in  claim 1 , wherein: 
 said means for identifying comprises means for monitoring said first plasma step for an occurrence of said first endpoint using first and second techniques, said first technique being different from said second technique.    
     
     
         12 . A system, as claimed in  claim 11 , wherein: 
 said first and second techniques are each selected from the group consisting of means for determining when there is at least a first change in an impedance of said processing chamber, means for evaluating optical emissions of said plasma in said processing chamber over a first wavelength range at least a plurality of times during said first plasma step, and means for evaluating at least one individual wavelength of said plasma in said processing chamber at least a plurality of times during said first plasma step.    
     
     
         13 . A system, as claimed in  claim 1 , wherein: 
 said means for identifying comprises means for determining if there is at least a first change in an impedance of said processing chamber.    
     
     
         14 . A system, as claimed in  claim 13 , wherein: 
 said means for determining is based upon a change in at least a portion of optical emissions of said plasma in said processing chamber during said first plasma step.    
     
     
         15 . A system, as claimed in  claim 1 , wherein: 
 said means for identifying comprises means for evaluating at least one individual wavelength of said plasma in said processing chamber at least a plurality of times during said first plasma step.    
     
     
         16 . A method, as claimed in  claim 15 , wherein: 
 said means for evaluating at least one individual wavelength comprises using a technique selected from the group consisting of means for determining when a plot of intensity versus time of said at least one individual wavelength deviates by more than a predetermined amount from a predetermined equation, means for determining when a time rate of change of a slope of said plot of intensity versus time of said at least one individual wavelength deviates by more than a predetermined amount, and combinations thereof.    
     
     
         17 . A system, as claimed in  claim 1 , wherein said plasma process comprises a second plasma step which is different from said first plasma step, wherein a second endpoint of said second plasma step is when a second result of said second plasma step has been achieved, and wherein said computer-readable storage medium further comprises: 
 means for identifying an occurrence of said second endpoint from data on said second plasma step provided to said means for receiving data.    
     
     
         18 . A system for running at least a first plasma step, said system comprising: 
 a processing chamber comprising a window;    a first gas inlet and a first gas outlet fluidly interconnected with said processing chamber;    a plasma generator in said plasma chamber, wherein said first plasma step may be run in said processing chamber when said plasma generator is activated, and wherein there is a first endpoint of said first plasma step which is when said first plasma step has produced a first predetermined result;    means for evaluating a condition of said plasma in said processing chamber, wherein said condition is a cumulative result of all parameters having an effect on said plasma in said processing chamber; and    means for identifying an occurrence of said first endpoint of said first plasma step.