Electroplating apparatus for tailored uniformity profile

Patent metadata

Field	Value
Publication number	US-2016115611-A1
Application number	US-201614987170-A
Country	US
Kind code	A1
Filing date	Jan 4, 2016
Priority date	Nov 7, 2008
Publication date	Apr 28, 2016
Grant date	—

Abstract

Methods of electroplating metal on a substrate while controlling azimuthal uniformity, include, in one aspect, providing the substrate to the electroplating apparatus configured for rotating the substrate during electroplating, and electroplating the metal on the substrate while rotating the substrate relative to a shield such that a selected portion of the substrate at a selected azimuthal position dwells in a shielded area for a different amount of time than a second portion of the substrate having the same average arc length and the same average radial position and residing at a different angular (azimuthal) position. For example, a semiconductor wafer substrate can be rotated during electroplating slower or faster, when the selected portion of the substrate passes through the shielded area.

First claim

1 . A method of electroplating a metal on a cathodically biased substrate while controlling azimuthal uniformity, the method comprising:
(a) providing the substrate into an electroplating apparatus configured for rotating the substrate during electroplating, wherein the apparatus comprises an anode and a stationary auxiliary azimuthally asymmetric cathode; and (b) electroplating the metal on the substrate while rotating the substrate, and while providing power to the auxiliary azimuthally asymmetric cathode in correlation with the rotation of the substrate, such that the auxiliary azimuthally asymmetric cathode diverts plating current from a first portion of the substrate at a selected azimuthal position of the substrate differently than from a second portion of the substrate having the same average arc length and the same average radial position and residing at a different azimuthal angular position.

2 . The method of claim 1 , wherein the auxiliary azimuthally asymmetric cathode is C-shaped.

3 . The method of claim 1 , wherein the auxiliary azimuthally asymmetric cathode is in an azimuthal current flow confinement structure.

4 . The method of claim 1 , wherein the auxiliary azimuthally asymmetric cathode is housed in a separate chamber and the exposure of plating current to the auxiliary cathode is through at least one channel that diverts current into a region of the cell near the periphery of the substrate over an arc angle of less than about 120 degrees.

Assignees

• Novellus Systems Inc

Inventors

• Mayer Steven T
• Porter David W
• Buckalew Bryan L
• Rash Robert

Classifications

• H10P14/47

  Electrolytic deposition, i.e. electroplating; Electroless plating · CPC title

• H10W20/043

  for electroplating · CPC title

• C25D17/008

  Current shielding devices · CPC title

• C25D5/04

  Electroplating with moving electrodes · CPC title

• C25D21/10

  Agitating of electrolytes; Moving of racks · CPC title