Method and apparatus for treating fluids to reduce microbubbles

• US 20090045140A1
• Filed: 04/25/2006
• Published: 02/19/2009
• Est. Priority Date: 04/25/2005
• Status: Active Grant

• Current Assignee: Entegris Incorporated
• Original Assignee: Entegris Incorporated
• Inventors: Wu, Aiwen, Zahka, Joseph
• Granted Patent: US 8,777,189 B2
• Time in Patent Office: Days
• US Class Current: 210/718
• CPC Class Codes: B01D 19/0031 by filtration

Abstract

Versions of the invention include methods for reducing microbubbles in liquids treated by heat or mass exchange devices. The exchange devices may be conditioned by having gases in crevices and surfaces displaced by a liquid. The methods can be used to prepare liquids with reduced numbers of microbubbles.

Claims

1. An apparatus comprising:

an exchange device with one or more gas trapping surface features;

a housing for said exchange device, said housing having a liquid inlet and a liquid outlet;

a liquid treated by the exchange device in contact with the surface features of the exchange device;

said contact reduces amount of microbubbles in the liquid from said surface features of the exchange device to a lower amount than in the absence of said contact of the liquid with surface features of the exchange device.

2. The apparatus of claim 1 wherein the liquid in contact with the surface features of the exchange device displaced gas from the surface features of the exchange device.

3. The apparatus of claim 1 wherein the liquid in contact with the surface features of the exchange device comprises gas dissolved from the surface features of the exchange device into the liquid.

4. The apparatus of claim 1 further comprising a conduit to provide the treated liquid to a substrate.

5. The apparatus of claim 1 wherein the liquid has a different surface energy than the exchange device

6. The apparatus of claim 1 where the liquid is treated by mass exchange.

7. The apparatus of claim 1 further comprising a pump.

8. The apparatus of claim 1 where the contact results in fewer than 1 microbubble particle count greater than about 0.2 microns in size per milliliter of liquid treated after less than about 30 hold-up volumes of liquid has been treated by the exchange device.

9. A method comprising:

contacting one or more surface features of an exchange device with a liquid, said contacting lowers the number of microbubble particle counts in the liquid from the surface features to a lower number than in the absence of said contacting of the liquid with surface features of the exchange device.

10. The method of claim 9 wherein the contacting comprises displacing gas from the surface features of the exchange device.

11. The method of claim 9 wherein the contacting comprises dissolving gas from the surface features of the exchange device into the liquid.

12. The method of claim 9 wherein the surface energy of the exchange device and the liquid are different.

13. The method of claim 9 further comprising the act of exchanging mass, energy, or a combination of these between the liquid and exchange device.

14. The method of claim 10 further comprising the act of dispensing the liquid treated by the exchange device onto a substrate.

15. The method of claim 9 further comprising the act of pressurizing the liquid contacting the surfaces of the exchange device.

16. The method of claim 9 where the surface features comprise one or more crevices or pores that trap a gas.

17. The method of claim 9 where the liquid flows over the surface features of the exchange device.

18. The method of claim 9 where the liquid that contacts the exchange device is pumped.

19. The method of claim 9 where the exchange device has an area of greater than 100 cm².

20. A method comprising:

contacting one or more surface features of a porous membrane in a housing with a liquid used to treat a wafer, said contacting lowers the number of heterogeneously formed microbubble particle counts from the surface features of the porous membrane in the liquid to a lower number than in the absence of said contacting of the liquid with the surface features of the porous membrane; and

filtering the liquid.

21. The method of claim 20 wherein the contacting comprises displacing gas from the surface features of the porous membrane.

22. The method of claim 20 wherein the contacting comprises dissolving gas from the surface features of the porous membrane into the liquid.

23. The method of claim 20 where the liquid includes an organic solvent.

24. The method of claim 20 further comprising the act of dispensing the liquid onto a substrate.

25. The method of claim 20 further comprising the act of pressurizing the liquid covering the porous membrane.

26. The method of claim 20 where the porous membrane has a rated pore size of about 0.05 microns or less.

27. The method of claim 20 where the porous membrane has a rated pore size of about 0.01 microns or less.

28. The method of claim 20 wherein the liquid includes a surfactant.

29. The method of claim 20 wherein the liquid is used in a lithographic process.

30. The method of claim 24 where in the substrate comprises copper.