Method for Non-Contact Cleaning of a Surface

Abstract

A flame torch can be used to clean the surface of a contact-sensitive object, such as a glass optic, extremely thin workpiece, or semiconductor wafer by providing a reactive precursor gas to the feed gases of the torch. Reactive atom plasma processing can be used to clean the surface of a contaminant that chemically combines with the atomic radicals of the precursor without affecting the surface. The torch can also be used to modify the surface after cleaning, without transferring the object or engaging in any intermediate processing, by supplying a second reactive precursor that reacts with the surface itself. The flame torch can be used to shape, polish, etch, planarize, deposit, chemically modify and/or redistribute material on the surface of the object. This description is not intended to be a complete description of, or limit the scope of, the invention. Other features, aspects, and objects of the invention can be obtained from a review of the specification, the figures, and the claims.

1 . A method of cleaning a surface of a workpiece with a flame torch, comprising: 
 igniting a flame of the flame torch;    supplying a reactive precursor to the flame by way of a source generally arranged coaxially to the flame, the flame generating reactive species from the reactive precursor as the reactive precursor interacts with the flame; and    arranging the flame and the workpiece so that the reactive species interact with the surface;    allowing the reactive species to chemically combine with a contaminant on the surface to cause the contaminant to leave the surface.    
     
     
         2 . The method of  claim 1 , wherein: 
 the contaminant is a first contaminant, and    a second contaminant on the surface with which the reactive species interacts does not chemically combine with the reactive species.    
     
     
         3 . The method of  claim 1 , wherein: 
 the reactive species includes at least one atomic radical.    
     
     
         4 . The method of  claim 1 , further comprising: 
 supplying a source of fuel to the flame torch.    
     
     
         5 . The method of  claim 1 , further comprising: 
 supplying a source of oxidizer gas to the flame torch.    
     
     
         6 . The method of  claim 1 , further comprising: 
 altering a chemistry of the surface of the workpiece with the reactive species.    
     
     
         7 . The method of  claim 1 , further comprising: 
 shaping the surface with the flame.    
     
     
         8 . The method of  claim 1 , further comprising: 
 rotating the workpiece with respect to the flame torch.    
     
     
         9 . The method of  claim 1 , further comprising: 
 selecting a concentration of the reactive precursor to be introduced into the flame torch.    
     
     
         10 . The method of  claim 1 , wherein the flame torch has an outer tube and an inner tube; and further comprising: 
 introducing a process gas through the outer tube.    
     
     
         11 . The method of  claim 1 , further comprising: 
 operating the flame torch at about atmospheric pressure.    
     
     
         12 . The method of  claim 1 , further comprising: 
 polishing the surface of the workpiece with the flame.    
     
     
         13 . The method of  claim 1 , further comprising: 
 planarizing the surface of the workpiece with the flame.    
     
     
         14 . The method of  claim 1 , wherein the flame torch includes multiple heads from which respective flames extend; and further comprising: 
 arranging the respective flames and the workpiece so that the reactive species of each of the flames interacts with the surface, thereby increasing a rate of cleaning.    
     
     
         15 . A method of modifying a surface of a workpiece with a flame torch, comprising: 
 igniting a flame of the flame torch;    supplying a reactive precursor to the flame to generate reactive species from the reactive precursor; and    arranging the workpiece downstream from the reactive species so that the reactive species interact with a contaminant on the surface;    removing a gaseous phase product resulting from a chemical reaction between the reactive species and the contaminant.    
     
     
         16 . The method of  claim 15 , wherein: 
 the contaminant is a first contaminant, and    a second contaminant on the surface with which the reactive species interacts does not chemically react with the reactive species.    
     
     
         17 . The method of  claim 15 , wherein removing a gaseous phase product shapes the surface.  
     
     
         18 . The method of  claim 15 , wherein removing a gaseous phase product planarizes the surface.  
     
     
         19 . The method of  claim 15 , wherein removing a gaseous phase product polishes the surface.  
     
     
         20 . The method of  claim 15 , wherein removing a gaseous phase product cleans the surface.