Tuning electrodes used in a reactor for electrochemically processing a microelectronics 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 in a processing chamber, comprising: 
 determining a first set of processing parameters for depositing material into micro-features on the workpiece such that at least a substantially uniform current density is maintained at the surface of the workpiece during a feature filling stage of a plating cycle;    determining a second set of processing parameters for depositing additional material onto the workpiece to provide a specified thickness profile of a deposited layer during a bulk plating stage of the plating cycle subsequent to the feature filling stage;    contacting the surface of the microelectronic workpiece with an electrolytic fluid in the processing chamber while delivering a plurality of electrical currents to the workpiece via a corresponding plurality of electrodes in the processing chamber;    filling the micro-features by operating the processing chamber according to the first set of processing parameters while delivering the plurality of electrical currents through the corresponding electrodes; and    plating the deposited layer to the specified thickness profile by operating the processing chamber according to the second set of processing parameters while delivering the plurality of electrical currents through the corresponding electrodes.    
     
     
         102 . The method of  claim 101  wherein determining the first set of processing parameters comprises (a) measuring a physical property of a seed layer on the workpiece, and (b) selecting a plurality of electrical currents for delivery through the corresponding plurality of electrodes that compensates for non-uniformities in the seed layer.  
     
     
         103 . The method of  claim 101  wherein the first set of processing parameters comprises a plurality of electrical currents for delivery through the corresponding plurality of electrodes.  
     
     
         104 . The method of  claim 101  wherein determining the second set of processing parameters comprises (a) measuring a physical property of a layer plated on the workpiece after completing the feature filling stage, and (b) selecting a plurality of electrical currents for delivery through the corresponding plurality of electrodes that plates a layer having a desired thickness profile onto the workpiece.  
     
     
         105 . The method of  claim 104  wherein the desired thickness profile is at least a substantially flat surface across the workpiece.  
     
     
         106 . The method of  claim 104  wherein the desired thickness profile is a convex surface having a thickness greater at a central portion of the workpiece than at a perimeter portion of the workpiece.  
     
     
         107 . The method of  claim 101  wherein: 
 filling the micro-features comprises delivering a first set of electrical currents through corresponding electrodes in the processing chamber such that at least a substantially uniform current density is maintained at the surface of the workpiece while material is plated into the micro-features; and    plating the deposited layer comprises delivering a second set of electrical currents through the corresponding electrodes in the processing chamber such that the deposited layer has a desired thickness profile, and wherein the second set of electrical currents is greater than the first set of electrical currents.    
     
     
         108 . The method of  claim 107  wherein the desired thickness profile is at least a substantially flat surface across the workpiece.  
     
     
         109 . The method of  claim 107  wherein the desired thickness profile is a convex surface having a thickness greater at a central portion of the workpiece than at a perimeter portion of the workpiece.  
     
     
         110 . The method of  claim 107  wherein an electrical current delivered through an innermost one of the electrodes is greater than an electrical current delivered through an outermost one of the electrodes in the first set of electrical currents.  
     
     
         111 . The method of  claim 107  wherein an electrical current delivered through an innermost one of the electrodes is greater than an electrical current delivered through an outermost one of the electrodes in the second set of electrical currents.  
     
     
         112 . A method for electrochemically processing a microelectronic workpiece in a processing chamber, comprising: 
 determining a first set of processing parameters for depositing material into micro-features on the workpiece by (a) measuring a physical property of a seed layer on the workpiece, (b) selecting an initial first set of processing parameters for plating material into the micro-features, (c) depositing a fill layer onto the workpiece in accordance with the initial first set of processing parameters, (d) measuring a property of the fill layer, and (e) selecting a revised first set of processing parameters for filling the micro-features on the workpiece; and    determining a second set of processing parameters for forming a profiled layer having a desired thickness profile by (a) measuring a fill layer deposited onto the workpiece in accordance with the revised first set of processing parameters, (b) selecting an initial second set of processing parameters for forming the profiled layer, (c) depositing a profiled layer onto the workpiece in accordance with the initial second set of processing parameters, (d) measuring a property of the profiled layer, and (e) selecting a revised second set of processing parameters for forming the profiled layer to have the desired thickness profile.    
     
     
         113 . The method of  claim 112  wherein the revised first set of processing parameters comprises a revised first set of a plurality of electrical currents delivered through a corresponding plurality of electrodes in the processing chamber.  
     
     
         114 . The method of  claim 112  wherein the revised second set of processing parameters comprises a revised second set of a plurality of electrical currents delivered through a corresponding plurality of electrodes in the processing chamber.  
     
     
         115 . The method of  claim 113  wherein the revised second set of processing parameters comprises a revised second set of a plurality of electrical currents delivered through a corresponding plurality of electrodes in the processing chamber.  
     
     
         116 . The method of  claim 115 , further comprising filling micro-features on a plurality of subsequent workpieces by delivering a plurality of electrical currents through a corresponding plurality of electrodes in the processing chamber according to the revised first set of processing parameters.  
     
     
         117 . The method of  claim 115 , further comprising plating the profiled layer onto the workpiece by delivering a plurality of electrical currents through the corresponding plurality of electrodes in the processing chamber according to the revised second set of processing parameters.  
     
     
         118 . The method of  claim 115  wherein the desired profile is at least a substantially flat surface on the workpiece.  
     
     
         119 . The method of  claim 115  wherein the desired profile is a convex surface on the workpiece.