Electrolyte delivery and generation equipment

Patent metadata

Field	Value
Publication number	US-10011919-B2
Application number	US-201514921602-A
Country	US
Kind code	B2
Filing date	Oct 23, 2015
Priority date	May 29, 2015
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

An apparatus for automatically generating a metal-containing electrolyte (e.g., an electrolyte containing Sn 2+ ions and an acid) includes an anolyte chamber configured to house an active anode (e.g., a metallic tin anode), an anolyte, and a sensor (e.g., one or more sensors) measuring a concentration of metal ions in the anolyte; a catholyte chamber configured to house a hydrogen-generating cathode and a catholyte; and a controller having program instructions for processing data from the sensor and for automatically generating an electrolyte having metal ions in a target concentration range in the anolyte chamber. In some embodiments, the apparatus is in communication with an electroplating apparatus and is capable to deliver the generated electrolyte to the electroplating apparatus on demand. In some embodiments, a densitometer and a conductivity meter are together used as sensors, and the apparatus is configured to generate low alpha tin electrolyte containing an acid.

First claim

The invention claimed is:

1. An apparatus for generating an electrolyte containing metal ions, the apparatus comprising:
(a) an anolyte chamber configured to contain an active anode and an anolyte, wherein the apparatus is configured to electrochemically dissolve the active anode into the anolyte, and to thereby form the electrolyte containing metal ions, wherein the anolyte chamber comprises:
(i) an inlet for receiving a fluid;
(ii) an outlet for removing the anolyte; and
(iii) one or more sensors configured for measuring a concentration of metal ions in the anolyte;

(b) a first catholyte chamber separated from the anolyte chamber by a first anion permeable membrane, wherein the first catholyte chamber is configured to contain a first catholyte;
(c) a second catholyte chamber configured to contain a cathode and a second catholyte, wherein the second catholyte chamber is separated from the first catholyte chamber by a second anion permeable membrane, wherein the first catholyte chamber and the second catholyte chamber are fluidically connected through a fluidic conduit, wherein the fluidic conduit allows for transfer of the second catholyte from the second catholyte chamber to the first catholyte chamber.

2. The apparatus of claim 1 , wherein the first catholyte chamber and the second catholyte chamber are parts of a removable cathode-housing assembly, wherein the removable cathode-housing assembly is configured to be releasably inserted into the anolyte chamber.

3. The apparatus of claim 1 , wherein the apparatus is configured to deliver the first catholyte from the first catholyte chamber to the anolyte chamber through a fluidic conduit, and/or wherein the apparatus is configured to remove the first catholyte from the first catholyte chamber to a drain.

4. The apparatus of claim 1 , wherein the apparatus comprises a single piece metal anode.

5. The apparatus of claim 1 , wherein the anolyte chamber comprises an ion -permeable container for containing a plurality of metal pieces that serve as an anode.

6. The apparatus of claim 5 , wherein the anolyte chamber further comprises a receiving port for receiving a plurality of metal pieces into the ion-permeable container.

7. The apparatus of claim 6 , wherein the receiving port comprises a gravity fed hopper.

8. The apparatus of claim 6 , wherein the receiving port comprises a sensor configured to communicate to a system controller when the level of metal pieces in the receiving port is low.

9. The apparatus of claim 1 , wherein the apparatus comprises a hydrogen-generating cathode positioned in the second catholyte chamber.

10. The apparatus of claim 9 , wherein the apparatus comprises a diluent gas conduit configured to deliver a diluent gas to a space above the second catholyte, and to dilute hydrogen gas accumulating in that space, wherein the space above the second catholyte is covered with a first lid having one or more openings that allow for transfer of diluted hydrogen gas into a space above the first lid.

11. The apparatus of claim 10 , further comprising: a second lid over the first lid and spaced apart from the first lid such that there is a space between the first and the second lids; and a second diluent gas conduit configured to deliver a diluent gas to a space between the first and second lids and to move the diluted hydrogen gas from the space between the first and second lids towards an exhaust.

12. The apparatus of claim 1 , wherein the anolyte chamber comprises a cooling system.

13. The apparatus of claim 1 , wherein the anolyte chamber comprises a cooling system that is located in a cooling portion of the anolyte chamber away from the active anode.

14. The apparatus of claim 13 , further comprising a fluidic conduit and an associated pump configured to deliver the anolyte from the anolyte chamber outlet to the cooling portion of the anolyte chamber, wherein the anolyte chamber outlet is located proximate the active anode.

15. The apparatus of claim 1 , wherein the apparatus is configured to measure the concentration of metal ions in the anolyte with the one or more sensors, and to communicate the measurement to an apparatus controller.

16. The apparatus of claim 15 , wherein a single sensor is used for measuring the concentration of metal ions in the anolyte and the sensor is a densitometer.

17. The apparatus of claim 15 , wherein at least two sensors are used for measuring the concentration of metal ions in the anolyte, wherein the at least two sensors comprise a densitometer and a conductivity meter.

18. The apparatus of claim 17 , wherein the densitometer and the conductivity meter are further configured for measuring the concentration of acid in the anolyte.

19. The apparatus of claim 18 , wherein the conductivity meter is an inductive probe.

20. The apparatus of claim 1 , further comprising a sensor configured to measure a concentration of acid in the second catholyte.

21. The apparatus of claim 1 , wherein the apparatus comprises a controller having program instructions for automatically generating electrolyte having a concentration of metal ions in a target range.

22. The apparatus of claim 1 , further comprising a fluidic connection allowing for automated transfer of the anolyte from the anolyte chamber to an electrolyte storage tank, wherein the electrolyte storage tank is fluidically connected to an electroplating tool, and wherein the apparatus is configured to deliver the electrolyte from the electrolyte storage tank to the electroplating tool.

23. The apparatus of claim 1 , further comprising an accessible compartment configured for holding a replaceable source of an acid, wherein the replaceable source of an acid is fluidically connected with the inlet of the anolyte chamber, and said fluidic connection comprises an acid buffer tank, wherein the apparatus is configured to deliver the acid from the replaceable source of the acid to the acid buffer tank and from the acid buffer tank to the anolyte chamber.

24. The apparatus of claim 1 , wherein the anolyte chamber further comprises an anolyte recirculation loop.

Assignees

• Lam Res Corp

Inventors

• Mayer Steven T
• Kearns Gregory
• Abraham Richard G
• Ossowski Lawrence

Classifications

• C25D17/001

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

• C25B15/08

  Supplying or removing reactants or electrolytes; Regeneration of electrolytes · CPC title

• C25B1/00

  Electrolytic production of inorganic compounds or non-metals · CPC title

• C25D3/30

  of tin · CPC title

• C25D3/02 Primary

  from solutions (C25D5/34 - C25D5/46 take precedence) · CPC title