Tuning electrodes used in a reactor for electrochemically processing a microelectronic workpiece

Abstract

A facility for selecting and refining electrical parameters for processing a microelectronic workpiece in a processing chamber is described. The facility initially configures the electrical parameters in accordance with either a mathematical model of the processing chamber or experimental data derived from operating the actual processing chamber. After a workpiece is processed with the initial parameter configuration, the results are measured and a sensitivity matrix based upon the mathematical model of the processing chamber is used to select new parameters that correct for any deficiencies measured in the processing of the first workpiece. These parameters are then used in processing a second workpiece, which may be similarly measured, and the results used to further refine the parameters. In some embodiments, the facility analyzes a profile of the seed layer applied to a workpiece, and determines and communicates to a material deposition tool a set of control parameters designed to deposit material on the workpiece in a manner that compensates for deficiencies in the seed layer.

1 - 100 . (canceled)  
     
     
         101 . A method for electrolytically processing a microelectronic workpiece using a processing chamber, a first electrode in the processing chamber, and a second electrode concentric with the first electrode in the processing chamber, comprising: 
 contacting the surface of the microelectronic workpiece with an electrolytic fluid in the processing chamber;    filling features in the workpiece by delivering a first initial current to the first electrode and a second initial current to the second electrode during a first stage of a plating cycle for the workpiece; and    depositing additional material onto the workpiece during a second stage of the plating cycle by delivering a first bulk plating current to the first electrode and a second bulk plating current to the second electrode, wherein the first initial current is different than the first bulk plating current and the second initial current is different than the second bulk plating current.    
     
     
         102 . The method of  claim 101  wherein the first initial current is less than the first bulk plating current and the second initial current is less than the second bulk plating current.  
     
     
         103 . The method of  claim 101 , further comprising delivering the first initial current and the second initial current to provide at least a substantially uniform current density at the surface of the workpiece.  
     
     
         104 . The method of  claim 103 , further comprising delivering the first bulk plating current and the second bulk plating current to provide a bulk plated layer on the workpiece having a substantially uniformly flat thickness profile across the surface of the workpiece.  
     
     
         105 . The method of  claim 103 , further comprising delivering the first bulk plating current and the second bulk plating current to provide a bulk plated layer on the workpiece having a convex thickness profile that is thicker at the center of the workpiece than at the perimeter of the workpiece.  
     
     
         106 . The method of  claim 101  wherein the first initial current is greater than the second initial current, and wherein the first bulk plating current is greater than the second bulk plating current.  
     
     
         107 . The method of  claim 101  wherein the first initial current is less than the second initial current, and wherein the first bulk plating current is less than the second bulk plating current.  
     
     
         108 . A method for electrolytically processing a microelectronic workpiece using a processing chamber, a first electrode in the processing chamber, and a second electrode concentric with the first electrode in the processing chamber, comprising: 
 contacting the surface of the microelectronic workpiece with an electrolytic fluid in the processing chamber;    delivering a first set of electrical currents through the first and second electrodes during a first stage of a plating cycle for the workpiece; and    changing the first set of electrical currents to deliver a second set of electrical currents through the first and second electrodes during a second stage of the plating cycle for the workpiece, wherein the first set of electrical currents is less than the second set of electrical currents.    
     
     
         109 . The method of  claim 108 , wherein: 
 the first set of electrical currents includes a first initial current delivered through the first electrode and a second intial current delivered through the second electrode; and    the second set of electrical currents includes a first subsequent current delivered through the first electrode and a second subsequent current delivered through the second electrode.    
     
     
         110 . The method of  claim 109  wherein the first initial current is less than the first subsequent current and the second initial current is less than the second subsequent current.  
     
     
         111 . The method of  claim 108 , further comprising delivering the first set of electrical currents to provide at least a substantially uniform current density at the surface of the workpiece.  
     
     
         112 . The method of  claim 108 , further comprising delivering the second set of electrical currents to provide a bulk plated layer on the workpiece having a substantially uniformly flat thickness profile across the surface of the workpiece.  
     
     
         113 . The method of  claim 108 , further comprising delivering the second set of electrical currents to provide a bulk plated layer on the workpiece having a convex thickness profile that is thicker at the center of the workpiece than at the perimeter of the workpiece.  
     
     
         114 . A method for electrolytically processing a microelectronic workpiece using a processing chamber, a first electrode in the processing chamber, and a second electrode concentric with the first electrode in the processing chamber, comprising: 
 contacting the surface of the microelectronic workpiece with an electrolytic fluid in the processing chamber;    producing a uniform current density at the surface of the workpiece to deposit an initial layer onto the workpiece during an intial stage of a plating cycle by delivering a first initial current through the first electrode and delivering a second initial current through the second electrode; and    forming a profiled layer on the initial layer during a subsequent stage of the plating cycle by delivering a first profile current through the first electrode and delivering a second profile current through the second electrode, wherein the first initial current is different than the first profile current and the second initial current is different than the second profile current.    
     
     
         115 . The method of  claim 114  wherein the first and second initial currents are delivered through the first and second electrodes, respectively, while plating into micro-features on the workpiece.  
     
     
         116 . The method of  claim 115  wherein first and second profile currents are delivered through the first and second electrodes, respectively, to form a profiled layer having a substantially uniform thickness across the workpiece.  
     
     
         117 . The method of  claim 115  wherein the first and second profile currents are delivered through the first and second electrodes, respectively, to form a profiled layer having a convex thickness profile such that profiled layer is thicker at a central portion of the workpiece than at a perimeter portion of the workpiece.