Apparatus and method for electrochemically depositing metal on a semiconductor workpiece

Abstract

A process for metallization of a workpiece, such as a semiconductor workpiece. In an embodiment, an alkaline electrolytic copper bath is used to electroplate copper onto a seed layer, electroplate copper directly onto a barrier layer material, or enhance an ultra-thin copper seed layer which has been deposited on the barrier layer using a deposition process such as PVD. The resulting copper layer provides an excellent conformal copper coating that fills trenches, vias, and other microstructures in the workpiece. When used for seed layer enhancement, the resulting copper seed layer provide an excellent conformal copper coating that allows the microstructures to be filled with a copper layer having good uniformity using electrochemical deposition techniques. Further, copper layers that are electroplated in the disclosed manner exhibit low sheet resistance and are readily annealed at low temperatures.

1 - 73 . (canceled) 
   
   
       74 . A method of applying a metallization structure to a semiconductor wafer, comprising:
 providing a first semiconductor wafer having a dielectric layer, a plurality of submicron micro-recesses in the dielectric layer, a first layer that conforms to the submicron micro-recesses, and a copper seed layer that conforms to the first layer;   providing an input parameter related to the first semiconductor wafer to a computer;   automatically determining a set of current values to apply to a plurality of electrodes including a first current value for a first electrode and a second current value for a second electrode independent of the first electrode, wherein the set of current values is based on the input parameter;   electroplating copper onto the first wafer using the first and second current values for at least a portion of a plating cycle;   measuring the first wafer after electroplating the copper and determining a revised input value; and   automatically determining a revised set of current values based on the revised input value, wherein the revised set of current values include a revised first current value for the first electrode and a revised second current value for the second electrode.