Selective treatment of the surface of a microelectronic workpiece

Abstract

In a process for treating a workpiece such as a semiconductor wafer, a processing fluid is selectively applied or excluded from an outer peripheral margin of at least one of the front or back sides of the workpiece. Exclusion and/or application of the processing fluid occurs by applying one or more processing fluids to the workpiece while the workpiece and a reactor holding the workpiece are spinning. The flow rate of the processing fluids, fluid pressure, and/or spin rate are used to control the extent to which the processing fluid is selectively applied or excluded from the outer peripheral margin.

1 . A method for processing a microelectronic workpiece having a first side, a second side, and an outer perimeter joining the first and second sides at their periphery, comprising the steps of: 
 applying a film over the first side and over at least a portion of the outer perimeter; and    providing a processing fluid capable of removing the film over an outer margin of the second side while preventing the processing fluid from flowing over the second side except at the outer margin.    
     
     
         2 . The method of  claim 1  wherein the processing fluid flows over the first side and over the outer perimeter, as well as over the outer margin of the second side, so as to remove the thin film from the outer perimeter and to remove any contaminant from the first side.  
     
     
         3 . The method of  claim 1  wherein the thin film comprises copper.  
     
     
         4 . The method of  claim 1  wherein the thin film comprises material selected from the group consisting of: silicon nitride, silicon oxide, and polysilicon.  
     
     
         5 . The method of  claim 1  wherein the thin film comprises photoresist.  
     
     
         6 . The method of  claim 1  wherein the processing fluid comprises at least one of hydrofluoric acid and hydrogen peroxide.  
     
     
         7 . The method of  claim 1  wherein the processing fluid comprises a mixture of an acid and an oxidizing agent.  
     
     
         8 . The method of  claim 1  wherein the processing fluid comprises a mixture of sulfuric acid and hydrogen peroxide.  
     
     
         9 . The method of  claim 1  wherein the processing fluid comprises a mixture of sulfuric acid and amoniun persulfate.  
     
     
         10 . A process for treating a microelectronic workpiece having a first side, a second side, and an outer perimeter joining the first and second sides, comprising: 
 applying a barrier layer over the first side;    applying a seed layer over to the barrier layer;    applying a metallization layer over the seed layer;    providing an etching fluid over an outer margin of the first side;    preventing the etching fluid from flowing over areas of the first side within the outer margin, to remove the seed layer and metallization layer from the outer margin of the first side.    
     
     
         11 . A method for processing a microelectronic workpiece having a first side, a second side, and an outer perimeter, comprising the steps of: 
 applying a thin film over the first side and over at least a portion of the outer perimeter; and    performing a step for removing the thin film from the outer perimeter by applying a fluid to the outer perimeter and by confining the fluid to the outer perimeter.    
     
     
         12 . A process for treating a microelectronic workpiece having a first side, a second side, and an outer perimeter joining the first and second sides, comprising the steps of: 
 applying a film over the first side and over at least a portion of the outer perimeter;    providing a process liquid onto the second side, onto the outer perimeter, and onto an outer annular margin of the first side; and    preventing the fluid from contacting any area of the first side other than the outer annular margin by spinning the workpiece.    
     
     
         13 . The process of  claim 12  further comprising the step of providing a second process fluid onto the first side of the workpiece.  
     
     
         14 . A method for processing a microelectronic workpiece having a front side and a back side, comprising the steps of: 
 applying a first layer onto the front side of the workpiece;    applying a metal film onto the first layer radially inside of an annular outer edge of the front side of the workpiece; spinning the workpiece; and    applying a process liquid onto the workpiece while confining the process liquid to the backside of the workpiece and to the annular outer edge of the front side.    
     
     
         15 . The method of  claim 14  further comprising the steps of connecting electrical contacts onto the annular outer edge of the seed layer on the front side of the workpiece, and applying the metal film onto the seed layer by electroplating.  
     
     
         16 . The method of  claim 14  wherein the first layer comprises a seed layer.  
     
     
         17 . The method of  claim 16  further comprising the step of applying a barrier layer onto the front side of the workpiece before applying the seed layer.  
     
     
         18 . The method of  claim 14  further comprising the step of applying a second process fluid to the back side of the workpiece.  
     
     
         19 . The method of  claim 18  wherein the first process fluid comprises a liquid and the second process fluid comprises a gas.