Method and apparatus for processing a substrate with minimal edge exclusion

Abstract

An apparatus for processing a material on a surface of a wafer having a diameter includes a cavity defined by a peripheral wall terminating at a peripheral edge and having at least one lateral dimension smaller than the wafer diameter and at least one lateral dimension larger than the wafer diameter and configured to hold a process solution proximate to the peripheral edge such that the process solution will always contact a first wafer surface region, a head configured to hold the wafer above the cavity peripheral edge so that the surface of the wafer faces the cavity, and an electrical contact member positioned outside the cavity peripheral wall and configured to contact a second wafer surface region where the lateral dimension of the cavity is smaller than the wafer diameter and to maintain electrical contact with the wafer when the wafer is moved relative to the contact member. Advantages of the invention include substantially full surface treatment of the wafer.

1 . A system for depositing materials on a surface of a wafer having a maximum lateral dimension, the system comprising: 
 an anode, the anode being placed into a cavity that is defined by a peripheral wall terminating at a peripheral edge, wherein the wafer is supported above the peripheral edge of the cavity so that the surface of the wafer faces the cavity and wherein a lateral dimension of the peripheral edge is longer than the maximum lateral dimension of the wafer;    an electrolyte for filing the cavity up to the peripheral edge of the cavity such that the electrolyte always contacts a first region of the surface of the wafer; and    an electrical contact member for contacting a second region of the surface of the wafer through a recessed portion of the peripheral wall of the cavity, wherein the second region intermittently contacts the electrolyte when the wafer is rotated.