Systems and methods for shielding features of a workpiece during electrochemical deposition

Patent metadata

Field	Value
Publication number	US-2017191180-A1
Application number	US-201715400586-A
Country	US
Kind code	A1
Filing date	Jan 6, 2017
Priority date	Jan 6, 2016
Publication date	Jul 6, 2017
Grant date	—

Abstract

In one embodiment, an electroplating cell for depositing a metal onto a surface of a substrate includes an electroplating chamber configured to receive an electrolyte containing metal ions and a substrate having a surface disposed to contact the electrolyte, wherein the surface of the substrate is configured to serve as a cathode and wherein the surface of the substrate includes an anomaly region at or near the outer perimeter of the surface of the substrate, an anode disposed in the electrolyte chamber, a shielding device disposed between the cathode and the anode to shield the anomaly section, an oscillator configured to impart a relative oscillation between the cathode and the shielding device, and a power source to cause an electric field between the anode and the cathode.

First claim

The embodiments of the disclosure in which an exclusive property or privilege is claimed are defined as follows:

1 . An electroplating cell for depositing a metal onto a surface of a substrate, comprising:
an electroplating chamber configured to receive an electrolyte containing metal ions and a substrate having a surface disposed to contact the electrolyte, wherein the surface of the substrate is configured to serve as a cathode and wherein the surface of the substrate includes an anomaly region at or near the outer perimeter of the surface of the substrate; an anode disposed in the electrolyte chamber; a shielding device disposed between the cathode and the anode to shield the anomaly section; an oscillator configured to impart a relative oscillation between the cathode and the shielding device; and a power source to cause an electric field between the anode and the cathode.

2 . The electroplating cell of claim 1 , wherein the shielding device is shaped to have an outer ring and an extension section extending inwardly from the outer ring.

3 . The electroplating cell of claim 2 , wherein the extension section extends inwardly from the outer ring in the range of about 5 mm to about 25 mm of the radial distance of the outer ring.

4 . The electroplating cell of claim 2 , wherein the extension section has an angular length in the range of about 2 degrees to about 35 degrees.

5 . The electroplating cell of claim 2 , wherein the extension section of the shielding device is shaped and sized to substantially align with the shape of the anomaly region.

6 . The electroplating cell of claim 1 , wherein the oscillator is configured to oscillate the cathode, and wherein the shielding device is a fixed shielding device.

7 . The electroplating cell of claim 1 , further comprising a mixing device for mixing the electrolyte.

8 . The electroplating cell of claim 6 , wherein the shielding device is located between the mixing device and the substrate, between the mixing device and the anode, or is integrated into the mixing device.

9 . The electroplating cell of claim 6 , wherein the oscillator is configured to oscillate the cathode, and wherein the shielding device moves with the mixing device.

10 . The electroplating cell of claim 9 , wherein the oscillator is configured to oscillate the mixing device.

11 . A method of electroplating a metal onto a surface of a substrate in an electroplating chamber configured to receive an electrolyte containing metal ions, an anode, and a substrate having a surface disposed to contact the electrolyte, wherein the surface of the substrate is configured to serve as a cathode, and wherein the surface of the substrate includes an anomaly region at or near the outer perimeter of the surface of the substrate, the method comprising:
providing a shielding device in an electrolyte chamber wherein the shielding device is configured to shield the anomaly region; imparting an electric field between the anode and the cathode; and imparting a relative oscillation between the cathode and the shielding device.

12 . The method of claim 11 , wherein imparting a relative oscillation between the surface and the shielding device includes oscillating the cathode relative to a fixed shielding device.

13 . The method of claim 11 , wherein imparting a relative oscillation between the surface and the shielding device includes running a plurality of oscillation periods.

14 . The method of claim 13 , further comprising rotating the cathode for at least a portion of the time between sequential oscillation periods.

15 . The method of claim 11 , wherein the shielding device is shaped and sized to substantially align with the shape of the anomaly region.

16 . The method of claim 11 , further comprising mixing the electrolyte with a mixing device.

17 . The method of claim 16 , wherein the shielding device is integrated into the mixing device.

18 . The method of claim 16 , wherein imparting a relative oscillation between the surface and the shielding device includes oscillating the mixing device relative to a rotating cathode.

19 . A device for shielding a surface of a substrate in an electroplating chamber for electroplating a metal on to the surface of the substrate, the electroplating chamber configured to receive an electrolyte containing metal ions, an anode, and a substrate having a surface disposed to contact the electrolyte, wherein the surface of the substrate is configured to serve as a cathode, and wherein the surface of the substrate includes an anomaly region at or near the outer perimeter of the surface of the substrate, the device comprising:
an outer perimeter configured for alignment with the outer perimeter of the substrate; and an extension section extending inwardly from the outer perimeter in the range of about 5 mm to about 25 mm of the radial distance of the outer ring.

20 . The device of claim 19 , further including mixing fins and channels.

Assignees

• Applied Materials Inc

Inventors

• Bergman Eric J
• Dennison Jeffrey J
• Bernt Marvin L

Classifications

• C25D21/10

  Agitating of electrolytes; Moving of racks · CPC title

• C25D5/022 Primary

  using masking means · CPC title

• C25D5/04

  Electroplating with moving electrodes · CPC title

• C25D17/12

  Shape or form (C25D17/14 takes precedence) · CPC title

• C25D17/002 Primary

  Cell separation, e.g. membranes, diaphragms · CPC title