Magnetic structure for metal plating control

Patent metadata

Field	Value
Publication number	US-11230791-B2
Application number	US-201916731169-A
Country	US
Kind code	B2
Filing date	Dec 31, 2019
Priority date	Aug 21, 2013
Publication date	Jan 25, 2022
Grant date	Jan 25, 2022

Abstract

Among other things, one or more systems and techniques for promoting metal plating profile uniformity are provided. A magnetic structure is positioned relative to a semiconductor wafer that is to be electroplated with metal during a metal plating process. In an embodiment, the magnetic structure applies a force that decreases an edge plating current by moving metal ions away from a wafer edge of the semiconductor wafer. In an embodiment, the magnetic structure applies a force that increases a center plating current by moving metal ions towards a center portion of the semiconductor wafer. In this way, the edge plating current has a current value that is similar to a current value of the center plating current. The similarity between the center plating current and the edge plating current promotes metal plating uniformity.

First claim

What is claimed is:

1. A system for promoting metal plating profile uniformity, comprising:
a plating cell configured to contain a semiconductor wafer, wherein, when the semiconductor wafer is disposed within the plating cell, a first surface of the semiconductor wafer faces an anode;
a magnetic structure disposed within the plating cell between the anode and the semiconductor wafer, wherein the magnetic structure is configured to modify an edge plating current associated with a metal plating process for the semiconductor wafer; and
a magnet movement component configured to move the magnetic structure in a first direction parallel to the first surface of the semiconductor wafer.

2. The system of claim 1 , wherein the magnet movement component is configured to move the magnetic structure in a second direction perpendicular to the first surface of the semiconductor wafer.

3. The system of claim 1 , wherein:
the magnetic structure is ring-shaped and has an inner diameter and an outer diameter, and
the inner diameter is greater than a diameter of the semiconductor wafer.

4. The system of claim 1 , wherein the magnetic structure is an electromagnet.

5. The system of claim 1 , wherein the magnetic structure is a permanent magnet.

6. The system of claim 1 , comprising:
a magnet strength component configured to vary at least one of a power or a current supplied to the magnetic structure.

7. The system of claim 1 , wherein the plating cell is configured to contain an electrolyte solution.

8. The system of claim 7 , wherein the electrolyte solution comprises metal ions.

9. The system of claim 1 , wherein the magnetic structure defines a continuous ring.

10. A system for promoting metal plating profile uniformity, comprising:
a plating cell configured to contain a semiconductor wafer;
a magnetic structure disposed between an anode and the semiconductor wafer, wherein the magnetic structure is configured to modify an edge plating current associated with a metal plating process for the semiconductor wafer; and
a magnet movement component configured to move the magnetic structure relative to the semiconductor wafer in a first direction parallel to a first surface of the semiconductor wafer facing the anode.

11. The system of claim 10 , wherein the magnet movement component is configured to move the magnetic structure in a second direction perpendicular to the first surface of the semiconductor wafer facing the anode.

12. The system of claim 10 , wherein the magnetic structure is disposed within the plating cell.

13. The system of claim 10 , wherein:
the magnetic structure is ring-shaped and has an inner diameter and an outer diameter, and
the inner diameter is greater than a diameter of the semiconductor wafer.

14. The system of claim 10 , comprising:
a magnet strength component configured to vary at least one of a power or a current supplied to the magnetic structure.

15. The system of claim 10 , wherein the plating cell is configured to contain an electrolyte solution.

16. The system of claim 15 , wherein the electrolyte solution comprises metal ions.

17. The system of claim 10 , wherein the magnetic structure defines a continuous ring.

18. A system for promoting metal plating profile uniformity, comprising:
a plating cell configured to contain a semiconductor wafer within an electrolyte solution comprising metal ions;
a magnetic structure disposed between an anode and the semiconductor wafer, wherein the magnetic structure is configured to modify an edge plating current associated with a metal plating process for the semiconductor wafer; and
a magnet movement component configured to move the magnetic structure relative to the semiconductor wafer in a first direction parallel to a first surface of the semiconductor wafer facing the anode.

19. The system of claim 18 , wherein the magnet movement component is configured to move the magnetic structure in a second direction perpendicular to the first surface of the semiconductor wafer.

20. The system of claim 18 , wherein the magnetic structure is disposed within the plating cell.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Tsai Ming-Chin
• Kao Chung-En
• Lu Victor Y

Classifications

• C25D17/001

  Apparatus specially adapted for electrolytic coating of wafers, e.g. semiconductors or solar cells · CPC title

• C25D5/007

  Electroplating using magnetic fields, e.g. magnets · CPC title

• C25D17/007 Primary

  Current directing devices · CPC title

• C25D7/123

  Semiconductors first coated with a seed layer or a conductive layer · CPC title

• C25D5/006

  Chemistry & Metallurgy · mapped topic