Systems and methods for removing contaminants in electroplating systems

Patent metadata

Field	Value
Publication number	US-2019345624-A1
Application number	US-201916407421-A
Country	US
Kind code	A1
Filing date	May 9, 2019
Priority date	May 9, 2018
Publication date	Nov 14, 2019
Grant date	—

Abstract

Electroplating systems according to the present technology may include a two-bath electroplating chamber including a separator configured to provide fluid separation between a first bath configured to maintain a catholyte during operation and a second bath configured to maintain an anolyte during operation. The system may include a catholyte tank fluidly coupled with the first bath of the two-bath electroplating chamber. The system may also include a contaminant retrieval system configured to remove contaminant ions from the catholyte.

First claim

What is claimed is:

1 . An electroplating system comprising:
a two-bath electroplating chamber including a separator configured to provide fluid separation between a first bath configured to maintain a catholyte during operation and a second bath configured to maintain an anolyte during operation; a catholyte tank fluidly coupled with the first bath of the two-bath electroplating chamber; and a contaminant retrieval system configured to remove contaminant ions from the catholyte.

2 . The electroplating system of claim 1 , wherein the contaminant retrieval system comprises a vessel positioned fluidly inline between the first bath and the catholyte tank.

3 . The electroplating system of claim 2 , wherein the vessel comprises an anode and a cathode electrically coupled with a power supply.

4 . The electroplating system of claim 3 , wherein the anode comprises a first material that is consumable or inert to the catholyte.

5 . The electroplating system of claim 4 , wherein the catholyte comprises a solution including tin, wherein the contaminant ions comprise copper, and wherein the first material comprises tin.

6 . The electroplating system of claim 4 , wherein the first material comprises a material inert to the catholyte and more noble than copper.

7 . The electroplating system of claim 3 , wherein the power supply is configured to operate at a voltage below a plating potential for tin within the electroplating system.

8 . The electroplating system of claim 7 , wherein the power supply is configured to operate at a voltage above a plating potential for copper within the electroplating system.

9 . The electroplating system of claim 2 , wherein the vessel comprises a packed bed of tin-containing particles.

10 . The electroplating system of claim 1 , wherein the contaminant retrieval system comprises a packed bed of tin-containing particles positioned in the catholyte tank.

11 . A method of removing copper contaminants from a tin-containing catholyte within an electroplating system, the method comprising:
flowing the catholyte from an electroplating chamber to a catholyte tank, passing the catholyte across a tin-containing material, and reducing the copper contaminants from the catholyte.

12 . The method of removing copper contaminants from a tin-containing catholyte within an electroplating system of claim 11 , wherein the tin-containing material comprises an anode of an anode-cathode pair of electrically coupled electrodes.

13 . The method of removing copper contaminants from a tin-containing catholyte within an electroplating system of claim 12 , wherein the anode and cathode are driven at a voltage below a tin plating potential and above a copper plating potential.

14 . The method of removing copper contaminants from a tin-containing catholyte within an electroplating system of claim 12 , wherein the cathode comprises tin or a material more noble than copper.

15 . The method of removing copper contaminants from a tin-containing catholyte within an electroplating system of claim 12 , wherein the tin-containing material is maintained in a vessel positioned between and fluidly coupled with the electroplating chamber and the catholyte tank.

16 . The method of removing copper contaminants from a tin-containing catholyte within an electroplating system of claim 11 , wherein the tin-containing material comprises a packed column of the tin-containing material.

17 . The method of removing copper contaminants from a tin-containing catholyte within an electroplating system of claim 11 , wherein the tin-containing material is disposed within the catholyte tank.

18 . An electroplating system comprising:
an electroplating chamber; an electrolyte tank fluidly coupled with the electroplating chamber and configured to maintain an electrolyte; a tin-containing electrolyte including copper ions; and a contaminant retrieval system configured to remove the copper ions from the electrolyte, wherein the contaminant retrieval system comprises a single component system of a tin-containing material, or a dual component system of a tin-containing material or a material more noble than copper on the electromotive force series.

19 . The electroplating system of claim 18 , wherein the contaminant retrieval system comprises a vessel positioned between the electroplating chamber and the electrolyte tank, and wherein the vessel houses the single component system or the dual component system.

20 . The electroplating system of claim 18 , wherein the contaminant retrieval system is configured in operation to maintain an increase in copper ion concentration within the electrolyte below about 1 ppm per five thousand wafers processed.

Assignees

• Applied Materials Inc

Inventors

• Roh Kwan Wook
• Mchugh Paul
• Lee Sam
• Hanson Kyle M
• Bernt Marvin L
• Kim Bioh

Classifications

• C25D3/30

  of tin · CPC title

• C25D21/18 Primary

  of electrolytes (C25D21/22 takes precedence) · CPC title

• C25D5/08

  Electroplating with moving electrolyte e.g. jet electroplating {(using locally applied jets of electrolyte C25D5/026)} · CPC title

• C25D3/38

  of copper · CPC title

• C25D5/22 Primary

  Electroplating combined with mechanical treatment during the deposition · CPC title