Method and apparatus for copper plating using electroless plating and electroplating

Abstract

A reactor for plating a metal onto a surface of a workpiece is set forth. The reactor comprises a reactor bowl including an electroplating solution disposed therein and an anode disposed in the reactor bowl in contact with the electroplating solution. A contact assembly is spaced from the anode within the reactor bowl. The contact assembly includes a plurality of contacts disposed to contact a peripheral edge of the surface of the workpiece to provide electroplating power to the surface of the workpiece. The contacts execute a wiping action against the surface of the workpiece as the workpiece is brought into engagement therewith The contact assembly also including a barrier disposed interior of the plurality of contacts. The barrier includes a member disposed to engage the surface of the workpiece to assist in isolating the plurality of contacts from the electroplating solution. In one embodiment, the plurality of contacts are in the form of discrete flexures while in another embodiment the plurality of contacts are in the form of a Belleville ring contact. A flow path may be provided in the contact assembly for providing a purging gas to the plurality of contacts and the peripheral edge of the workpiece. The purging gas may be used to assist in the formation of the barrier of the contact assembly. A combined electroplating/electroless plating tool and method are also set forth.

1 - 42 . (canceled)  
   
   
       43 . A reactor for electrochemically processing a workpiece, comprising: 
 a bowl configured to contain a processing solution;    an electrode in the bowl and configured to contact the processing solution; and    a head assembly having a rotational motor and a workpiece holder attached to the rotational motor to rotate about a rotational axis, wherein the workpiece holder comprises (a) a conductive support member having an opening configured to receive a workpiece in a workpiece plane, (b) a conductive ring member attached to the conductive support member, and (c) a plurality of contact members having first portions projecting inwardly from the ring member and distal portions projecting from the first portions to be inclined at an angle with respect to the rotational axis to slope toward the workpiece plane.    
   
   
       44 . The reactor of  claim 43  wherein the ring member comprises an arcuate band attached to the conductive support member.  
   
   
       45 . The reactor of  claim 44  wherein the acruate band comprises a conical member inclined at an angle sloping toward the workpiece plane with decreasing distance from the rotational axis.  
   
   
       46 . The reactor of  claim 44  wherein the band has a truncated conical shape.  
   
   
       47 . The reactor of  claim 44  wherein the contact members project from the arcuate band radially inwardly relative to the rotational axis.  
   
   
       48 . The reactor of  claim 44  wherein the contact members project from the arcuate band at a swept angle relative to the rotational axis.  
   
   
       49 . The reactor of  claim 43  wherein the ring member comprises a continuous single-piece band.  
   
   
       50 . The reactor of  claim 43  wherein the ring member comprises a first band segment having a first circumferential portion of a circle and a separate second band segment having a second circumferential portion of the circle.  
   
   
       51 . The reactor of  claim 43  wherein the workpiece holder further comprises a barrier having an annular lip configured to seal against a surface of a workpiece at the workpiece plane inwardly from the contact members.  
   
   
       52 . The reactor of  claim 43  wherein the support member is composed of a conductive material and the ring member comprises a metal Belleville ring inclined at an angle sloping toward the workpiece plane with decreasing distance from the rotational axis.