Apparatus and method for electroplating a wafer surface

Abstract

The present invention provides for a method of electroplating a wafer surface comprising introducing a plating liquid to the wafer surface in a chamber and rotating the wafer about an axis of rotation passing through the surface to be plated, and including the further step of moving the wafer such that its axis of rotation is itself caused to rotate about a second axis of rotation.

1 . A method of electroplating a wafer surface comprising introducing a plating liquid to the wafer surface in a chamber and rotating the wafer about an axis of rotation passing through the wafer surface to be plated, characterized by the step of further moving the wafer such that its axis of rotation is itself caused to rotate about a second axis of rotation.  
     
     
         2 . A method as claimed in  claim 1 , wherein the wafer is located between the said axes of rotation and outer walls of the chamber.  
     
     
         3 . A method as as claimed in  claim 1 , wherein the wafer is located on a substantially circular wafer support and the wafer's axis of rotation passes through the centre of the circular support.  
     
     
         4 . A method as claimed in  claim 3 , wherein the said substantially circular wafer support holding the wafer is itself arranged to be supported on a circular support plate arranged to rotate about the said second axis of rotation.  
     
     
         5 . A method as claimed in  claim 4 , wherein the said substantially circular wafer support, the wafer and the said circular support plate are driven to rotate as rotating eccentric circles.  
     
     
         6 . A method as claimed in  claim 1 , wherein the respective rotations about the said axes of rotation are in opposite directions.  
     
     
         7 . A method as claimed in  claim 1 , wherein the said second axis of rotation is substantially parallel to the said axis of rotation passing through the wafer.  
     
     
         8 . An apparatus for electroplating a wafer surface, including a chamber for housing a wafer and into which plating liquid is to be introduced, driven support means for supporting the wafer and rotating the same about an axis passing through the wafer surface to be plated, and characterized by further driven support means arranged to move the wafer support such that its axis of rotation itself rotates about a second axis of rotation within the chamber.  
     
     
         9 . An apparatus as claimed in  claim 8 , including means for locating the wafer between the said second axes of rotation and an outer region of the chamber.  
     
     
         10 . An apparatus as as claimed in  claim 8 , wherein the driven support means for supporting the wafer comprises a circular member.  
     
     
         11 . An apparatus as claimed in  claim 10 , wherein the said further driven support means comprises a circular member.  
     
     
         12 . An apparatus as claimed in  claim 11 , wherein the two circular members are arranged as eccentric circular members.  
     
     
         13 . An apparatus as claimed in  claim 8 , wherein the respective rotations around the axes of rotation are arranged to be in opposite directions.  
     
     
         14 . An apparatus as claimed in  claim 8 , wherein the said second axis of rotation is substantially parallel to the said axis of rotation passing through the wafer.  
     
     
         15 . Support apparatus for supporting a wafer having a surface to be plated, comprising first means arranged for supporting the wafer and for the rotation of the wafer about an axis of rotation passing through the wafer surface to be plated, and characterized by second means arranged for supporting the said first means and for moving the said first means in a manner such that the said axis of rotation of the first means rotates about a second axis of rotation.  
     
     
         16 . An apparatus for electroplating a wafer surface, including a chamber for housing a wafer and into which plating liquid is to be introduced, driven support means for supporting the wafer and rotating the same about an axis passing through the wafer surface to be plated, and characterized by further driven support means arranged to move the wafer support such that its axis of rotation itself rotates about a second axis of rotation within the chamber, wherein the respective rotations around the axes of rotation are arranged to be in opposite directions, the apparatus configured to implement a method of electroplating a wafer surface comprising introducing a plating liquid to the wafer surface in a chamber and rotating the wafer about an axis of rotation passing through the wafer surface to be plated, characterized by the step of further moving the wafer such that its axis of rotation is itself caused to rotate about a second axis of rotation, wherein the said second axis of rotation is substantially parallel to the said axis of rotation passing through the wafer.  
     
     
         17 . Support apparatus as claimed in  claim 15 , wherein the said second axis is substantially parallel to the axis of rotation of the said first means.  
     
     
         18 . A method of manufacturing an electronic device comprising the step of electroplating a wafer surface according to  claim 1 .  
     
     
         19 . A method of manufacturing an electronic device comprising the step of electroplating a wafer surface according to  claim 2 .  
     
     
         20 . A method of manufacturing an electronic device comprising the step of electroplating a wafer surface according to  claim 3.