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 - 8 . (canceled)  
     
     
         9 . A method in a computing system for providing closed-loop control of a process for applying a coating material to a series of workpieces to produce a coating layer of the coating material, comprising: 
 (a) receiving a coating profile specifying one or more attributes of the coating layer to be produced on the workpieces;    (b) designating a first set of coating parameters for use in coating a first workpiece;    (c) identifying a first set of discrepancies between attributes of the coating layer produced on the first workpiece using the first set of coating parameters and the attributes specified by the coating profile;    (d) determining a first set of modifications to the first set of coating parameters expected to reduce the identified first set of discrepancies;    (e) modifying the first set of coating parameters in accordance with the determined first set of modifications to produce a second set of coating parameters;    (f) designating the second set of coating parameters for use in coating a second workpiece; and    (g) repeating (c)-(f) for subsequent workpieces in the series until the identified set of discrepancies falls within a selected tolerance.    
     
     
         10 . The method of  claim 9 , further comprising, after (g), designating the most recently-produced set of coating parameters for use in coating subsequent workpieces.  
     
     
         11 . The method of  claim 9  wherein each workpiece is a silicon wafer.  
     
     
         12 . The method of  claim 9  wherein the coating material is a conductor.  
     
     
         13 . The method of  claim 9  wherein the coating material is copper.  
     
     
         14 . The method of  claim 9  wherein the process is performed in an electrolysis chamber having a plurality of anodes, and wherein at least a portion of the coating parameters are currents to transmit through identified anodes among the plurality of anodes.  
     
     
         15 . The method of  claim 9  wherein at least a portion of the attributes of the coating layer to be produced on the workpieces specified by the coating profile are target thicknesses of the coating layer in selected regions on the workpiece.  
     
     
         16 . The method of  claim 15  wherein the discrepancies identified in (c) correspond to differences between thicknesses measured in the selected regions on the coated workpiece and the target thicknesses specified by the coating profile for the selected regions on the workpiece.  
     
     
         17 . The method of  claim 15 , further comprising: 
 generating a set of predicted coating thicknesses in the selected regions on the first workpiece based upon the first set of coating parameters;    receiving an indication of thicknesses measured in the selected regions on the coated first workpiece;    computing a difference between the predicted coating thicknesses and the indicated measured thicknesses; and    subtracting the computed difference from the determined first set of modifications before using the first set of modifications to modify the first set of coating parameters.    
     
     
         18 . The method of  claim 15  wherein each of the workpieces bears a seed layer, the method further comprising: 
 for each the first and second workpieces, receiving an indication of seed layer thicknesses measured in the selected regions on the workpiece before the workpiece is coated; and    before designating the second set of coating parameters for use in coating a second workpiece, further adjusting the second set of coating parameters in to adjust for differences between the measured thicknesses of the first and second workpieces.    
     
     
         19 . The method of  claim 9  wherein the coating process is electrolytic deposition.  
     
     
         20 . The method of  claim 9  wherein the coating process is electrophoretic deposition.  
     
     
         21 . The method of  claim 9  wherein the coating process is chemical vapor deposition.  
     
     
         22 . The method of  claim 9  wherein the coating process is physical vapor deposition.  
     
     
         23 . The method of  claim 9  wherein the coating process is electron beam atomization.  
     
     
         24 . The method of  claim 9  wherein (d) utilizes a sensitivity matrix mapping changes in attributes to changes in coating parameters expected to produce those attribute changes.  
     
     
         25 . A computer-readable medium whose contents cause a computing system to provide closed-loop control of a process for applying a coating material to a series of workpieces to produce a coating layer of the coating material by: 
 (a) receiving a coating profile specifying one or more attributes of the coating layer to be produced on the workpieces;    (b) designating a first set of coating parameters for use in coating a first workpiece;    (c) identifying a first set of discrepancies between attributes of the coating layer produced on the first workpiece using the first set of coating parameters and the attributes specified by the coating profile;    (d) determining a first set of modifications to the first set of coating parameters expected to reduce the identified first set of discrepancies;    (e) modifying the first set of coating parameters in accordance with the determined first set of modifications to produce a second set of coating parameters; and    (f) designating the second set of coating parameters for use in coating a second workpiece.    
     
     
         26 . The computer-readable medium of  claim 25 , further comprising repeating (c)-(f) for subsequent workpieces in the series until the identified set of discrepancies falls within a selected tolerance.  
     
     
         27 - 100 . (canceled)  
     
     
         101 . The computer-readable medium of  claim 25 , further comprising measuring attributes of the coating layer produced on the first workpiece using the first set of coating parameters, and wherein the measured attributes are used to identify the first set of discrepancies.  
     
     
         102 . The computer-readable medium of  claim 101  wherein the measurement is performed immediately after the first workpiece is coated.  
     
     
         103 . The computer-readable medium of  claim 101  wherein the measurement is performed without first performing any processing operation with respect to the first workpiece subsequent to the coating of the first workpiece.  
     
     
         104 . A method in a computing system for providing closed-loop control of a process for applying a coating material to a series of workpieces to produce a coating layer of the coating material, comprising: 
 (a) receiving a coating profile specifying one or more attributes of the coating layer to be produced on the workpieces;    (b) designating a first set of coating parameters for use in coating a first workpiece;    (c) identifying a first set of discrepancies between attributes of the coating layer produced on the first workpiece at least partially using the first set of coating parameters and the attributes specified by the coating profile;    (d) determining a first set of modifications to the first set of coating parameters expected to reduce the identified first set of discrepancies;    (e) modifying the first set of coating parameters in accordance with the determined first set of modifications to produce a second set of coating parameters; and    (f) designating the second set of coating parameters for use in coating a second workpiece.    
     
     
         105 . The method of  claim 104 , further comprising repeating (c)-(f) for subsequent workpieces in the series until the identified set of discrepancies falls within a selected tolerance.  
     
     
         106 . The method of  claim 104 , further comprising measuring attributes of the coating layer produced on the first workpiece using the first set of caching parameters, and wherein the measured attributes are used to identify the first set of discrepancies.  
     
     
         107 . The method of  claim 106  wherein the measurement is performed immediately after the first workpiece is coated.  
     
     
         108 . The method of  claim 106  wherein the measurement is performed without first performing any processing operation with respect to the first workpiece subsequent to the coating of the first workpiece.