MAGNETIC STRUCTURE FOR METAL PLATING CONTROL

• US 20200131662A1
• Filed: 12/31/2019
• Published: 04/30/2020
• Est. Priority Date: 08/21/2013
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: TSAI, Ming-Chin, KAO, Chung-En, LU, Victor Y.
• Granted Patent: US 11,230,791 B2
• Time in Patent Office: Days
• CPC Class Codes: C25D 17/001 Apparatus specially adapted for electrolytic coating of wafers, e.g. semiconductors or solar cells
• CPC Class Codes: C25D 17/007 Current directing devices
• CPC Class Codes: C25D 5/007 Electroplating using magnetic fields, e.g. magnets
• CPC Class Codes: C25D 7/123 Semiconductors first coated with a seed layer or a conductive layer

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.

Claims

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; and

a magnetic structure disposed within the plating cell between the anode and the semiconductor wafer, wherein the magnetic structure is configured to modify at least one of an edge plating current or a center plating current associated with a metal plating process for the semiconductor wafer.

2. The system of claim 1, comprising:

a magnet movement component configured to move the magnetic structure in a direction parallel to the first surface of the semiconductor wafer.

3. The system of claim 1, comprising:

a magnet movement component configured to move the magnetic structure in a direction perpendicular to the first surface of the semiconductor wafer.

4. The system of claim 1, comprising:

a magnet movement component configured to;

move the magnetic structure in a first direction parallel to the first surface of the semiconductor wafer, and

move the magnetic structure in a second direction perpendicular to the first surface of the semiconductor wafer.

5. 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.

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

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

8. The system of claim 1, wherein the magnetic structure comprises a first magnetic portion and a second magnetic portion separated from the first magnetic portion.

9. 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.

10. A system for promoting metal plating profile uniformity, comprising:

a plating cell configured to contain a semiconductor wafer; and

a magnetic structure comprising a first magnetic portion and a second magnetic portion spaced apart from the first magnetic portion, wherein the magnetic structure is configured to modify at least one of an edge plating current or a center plating current associated with a metal plating process for the semiconductor wafer.

11. The system of claim 10, wherein:

when the semiconductor wafer is disposed within the plating cell, a first surface of the semiconductor wafer faces an anode, and

the first magnetic portion and the second magnetic portion are disposed within the plating cell between the anode and the semiconductor wafer.

12. The system of claim 10, wherein the first magnetic portion and the second magnetic portion are disposed outside of the plating cell such that, when the semiconductor wafer is disposed within the plating cell, a wall of the plating cell is disposed between the first magnetic portion and the semiconductor wafer and between the second magnetic portion and the semiconductor wafer.

13. The system of claim 10, comprising:

a magnet strength component configured to vary at least one of a power or a current supplied to at least of the first magnetic portion or the second magnetic portion.

14. The system of claim 10, comprising:

a magnet movement component configured to;

move the magnetic structure in a first direction parallel to a first surface of the semiconductor wafer when the semiconductor wafer is disposed within the plating cell, and

move the magnetic structure in a second direction perpendicular to the first surface of the semiconductor wafer when the semiconductor wafer is disposed within the plating cell.

15. 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.

16. A system for promoting metal plating profile uniformity, comprising:

a plating cell configured to contain a semiconductor wafer; and

a ring-shaped magnetic structure, wherein;

the ring-shaped magnetic structure has an inner diameter and an outer diameter, and

the inner diameter is greater than a diameter of the semiconductor wafer.

17. The system of claim 16, wherein:

when the semiconductor wafer is disposed within the plating cell, a first surface of the semiconductor wafer faces an anode, and

the ring-shaped magnetic structure is disposed between the anode and the semiconductor wafer.

18. The system of claim 16, comprising:

a magnet movement component configured to move the ring-shaped magnetic structure in a direction perpendicular to a first surface of the semiconductor wafer when the semiconductor wafer is disposed within the plating cell.

19. The system of claim 16, wherein the ring-shaped magnetic structure is disposed within the plating cell.

20. The system of claim 16, comprising:

a magnet strength component configured to vary at least one of a power or a current supplied to the ring-shaped magnetic structure.