Method and apparatus for removal of unwanted electroplating deposits

Abstract

An apparatus and associated method for removing deposits from a substrate. In one aspect, a system is provided which supplies etchant to an edge bead removal chamber. The apparatus includes an etchant delivery system, an etchant tank, a sensor, and a mixing tank.

1 . A point-of-use etchant preparation and delivery apparatus, comprising: 
 a chemical source;    a mixing module in fluid communication with the chemical source and configured for mixing two or more chemical received from the chemical source into an etchant; and    an edge bead removal chamber supply line coupled at one end to the mixing module.    
     
     
         2 . The apparatus of  claim 1 , wherein the chemical source comprises an acid storage member.  
     
     
         3 . The apparatus of  claim 1 , wherein the chemical source comprises a nitric acid storage member.  
     
     
         4 . The apparatus of  claim 1 , wherein the chemical source comprises a citric acid storage member.  
     
     
         5 . The apparatus of  claim 1 , wherein the chemical source comprises a sulfuric acid storage member.  
     
     
         6 . The apparatus of  claim 1 , wherein the chemical source comprises an oxidizer storage member.  
     
     
         7 . The apparatus of  claim 1 , wherein the mixing module further comprises a fluid-level sensor.  
     
     
         8 . The apparatus of  claim 7 , further comprising a controller communicably connected to the fluid-level sensor and configured to initiate an etchant mixing process within the mixing module in response to information received from the fluid-level sensor.  
     
     
         9 . The apparatus of  claim 1 , wherein the chemical source comprises an acid storage member and an oxidizer storage member.  
     
     
         10 . The apparatus of  claim 9 , wherein the acid storage member is a sulfuric acid storage member and the oxidizer storage member is a hydrogen peroxide storage member.  
     
     
         11 . A point-of-use etchant preparation and delivery apparatus, comprising: 
 a chemical source comprising an acid source and an oxidizer source;    a mixing module in fluid communication with the chemical source and configured for mixing an acid from the acid source and an oxidizer from the oxidizer source into an etchant;    a supply line coupled at one end to the mixing module; and    an edge bead removal chamber connected at another end of the supply line and comprising: 
 a substrate support member; and  
 a plurality of etchant delivery nozzles.  
   
     
     
         12 . The apparatus of  claim 11 , wherein the acid is citric acid.  
     
     
         13 . The apparatus of  claim 11 , wherein the acid is one of citric acid and sulfuric acid.  
     
     
         14 . The apparatus of  claim 11 , wherein the oxidizer is hydrogen peroxide and the acid is sulfuric acid.  
     
     
         15 . The apparatus of  claim 11 , wherein plurality of nozzles are circumferentially spaced around a periphery of the substrate support member.  
     
     
         16 . The apparatus of  claim 11 , further comprising a heating tank disposed inline with the supply line.  
     
     
         17 . The apparatus of  claim 11 , wherein the mixing module further comprises a fluid-level sensor.  
     
     
         18 . The apparatus of  claim 17 , further comprising a controller communicably connected to the fluid-level sensor and configured to initiate an etchant mixing process within the mixing module in response to information received from the fluid-level sensor.  
     
     
         19 . A method of preparing and delivering an etchant at a point of use, comprising: 
 flowing an acid from an acid source to a mixing module;    flowing an oxidizer from an oxidizer source to the mixing module;    mixing the oxidizer and acid in the mixing module to form an etchant;    flowing the etchant from the mixing module to an edge bead removal chamber; wherein the acid source, oxidizer source and edge bead removal chamber are each connected to the mixing module during each of the flowing and mixing steps.    
     
     
         20 . The method of  claim 19 , further comprising sensing a fluid level in the mixing module.  
     
     
         21 . The method of  claim 19 , wherein flowing the acid and flowing the oxidizer occur in response to sensing a fluid level in the mixing module.  
     
     
         22 . The method of  claim 19 , wherein the oxidizer is hydrogen peroxide and the acid is sulfuric acid.  
     
     
         23 . The method of  claim 19 , wherein the oxidizer is hydrogen peroxide and the acid is citric acid.  
     
     
         24 . The method of  claim 19 , further comprising heating the etchant.  
     
     
         25 . The method of  claim 19 , further comprising applying the etchant only to a peripherary of a substrate disposed in the edge bead removal chamber to remove material therefrom.  
     
     
         26 . The method of  claim 25 , further comprising, after applying the etchant only to the peripherary of the substrate: 
 spinning the substrate;    rinsing the substrate; and    drying the substrate.    
     
     
         27 . A method of processing a substrate having an electroplated material deposited thereon to remove unwanted deposits of electroplated material, the method comprising: 
 mixing an oxidizer and an acid in a mixing module to form an etchant;    flowing the etchant from the mixing module to an edge bead removal chamber;    applying the etchant only to a periphery of the substrate while rotatating the substrate in the edge bead removal chamber;    
     
     
         28 . The method of  claim 27 , further comprising, prior to mixing: 
 flowing the acid and flowing the oxidizer to the mixing module in response to sensing a fluid level in the mixing module.    
     
     
         29 . The method of  claim 27 , wherein the oxidizer is hydrogen peroxide and the acid is sulfuric acid.  
     
     
         30 . The method of  claim 27 , wherein the oxidizer is hydrogen peroxide and the acid is citric acid.  
     
     
         31 . The method of  claim 27 , further comprising heating the etchant.