Ex Parte EVANS - Page 7

          Appeal No. 2005-1220                                                        
          Application No. 09/270,606                                 Page 7           

          blanket polishing rate.3  Concerning those claimed polishing                
          rates, we note that each of those claimed rate terms employ a               
          term of degree (“substantially” or “approximating”), which terms            
          thus encompass a range of polishing (silicon dioxide layer high             
          and low structure area removal) rates.  In this regard,                     
          appellant’s specification furnishes graphs and descriptions                 
          thereof that reasonably make clear those claimed rate ranges                
          encompass rates significantly different than either a zero                  
          removal rate or a blanket removal rate, respectively.  For                  
          example, at page 5, line 2 through page 7, line 13, appellant’s             
          specification provides that (underlining supplied):                         
               If polishing using ceria slurry is carried out for a                   
               sufficiently long time, two important results occur:                   
               First, when the substrate surface becomes substantially                
               planarized, polishing characteristics revert back to                   
               more conventional behavior. Second, if silicon,                        
               polysilicon, or silicon nitride underlie the polished                  
               layer of silicon dioxide, they tend to act as a polish                 
               stop. These results are illustrated in FIGS. 6a-6d,                    
               which depict polishing characteristics for feature size                
               scales corresponding to FIGS. 3 and 5. Long term ceria                 
               polishing characteristics are illustrated generally at                 
               60. A high area rate 62 approximates blanket rate 20                   
               over time, while a low area rate 64 is close to zero.                  
               Convergence points 66 are reached in some instances,                   
               with a converged rate 68 being shown for those                         
               instances. Where an appropriate underlying material is                 
               present, a polish stop rate 70 is shown.                               
               3 A blanket polishing rate is defined in appellant’s                   
          specification as a removal rate that is obtained (measured) on an           
          unpatterned waiver.  See page 2, line 23 of appellant’s                     
          specification.                                                              



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