Brush for cleaning wafer

• US 20060151003A1
• Filed: 01/10/2005
• Published: 07/13/2006
• Est. Priority Date: 01/10/2005
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Liou, Huey-Chiang, Tregub, Alexander, Moinpour, Mansour
• Granted Patent: US 7,469,443 B2
• Time in Patent Office: Days
• US Class Current: 134/2
• CPC Class Codes: B08B 1/32 using rotary cleaning members
• CPC Class Codes: B08B 1/34 rotating about an axis parallel to the surface
• CPC Class Codes: B08B 3/04 Cleaning involving contact with liquid
• CPC Class Codes: H01L 21/67046 using mainly scrubbing means, e.g. brushes

Abstract

In a formulation of a wafer cleaning brush, forming a polymer solution with a plurality of nano-scale porogens or with a synthetic pore forming agent and curing the polymer solution to form a porous polymeric material.

Claims

1. A method, comprising:

forming a polymer solution with a plurality of nano-scale porogens;

coating a plurality of extremity portions of a plurality of nodules of a cleaning brush with the polymer solution; and

curing the polymer solution.

2. The method according to claim 1, wherein the curing of the polymer solution includes removing the nano-scale porogens to leave a plurality of nano-size pores.

3. The method according to claim 1, further comprising:

prior to the coating of the plurality of extremity portions, forming the nodules with a first porous polymeric material having at least a plurality of micro-size pores; and

wherein the curing of the polymer solution includes curing the polymer solution to form a second porous polymeric material having a plurality of nano-size pores.

4. The method according to claim 3, wherein the nano-size pores have a diameter of less than 1 um.

5. The method according to claim 3, wherein the micro-size pores have a diameter greater than 1 um.

6. The method according to claim 1, wherein the coating of the plurality of extremity portions includes dipping the cleaning brush into the polymer solution;

rolling the cleaning brush in the polymer solution; and

removing the cleaning brush from the polymer solution.

7. The method according to claim 1, wherein the polymer solution includes a polyvinyl alcohol.

8. A wafer cleaning brush, comprising:

a core;

a plurality of spaced-apart nodules disposed to protrude from the core;

each of the nodules having a first portion proximately located relative to the core and a second portion distally located relative to the core;

a selected one of the first and the second portions including a plurality of micro-size pores; and

the other one of the first and the second portions including a plurality of nano-size pores.

9. The wafer cleaning brush according to claim 8, wherein the selected one of the first and the second portions is the first portion and the other one of the first and the second portions is the second portion.

10. The wafer cleaning brush according to claim 9, wherein each of the nodules include a protrusion of a first porous polymeric material having the plurality of micro-size pores and a layer of a second porous polymeric material having the plurality of nano-size pores coated over a part of the protrusion to form the second portion, with the first portion being an exposed part of the protrusion not coated by the layer.

11. The wafer cleaning brush according to claim 10, wherein the first porous polymeric material is formed from a first mixture of a polyvinyl alcohol and a porous forming agent;

and the second porous polymeric material is formed from a second mixture of the polyvinyl alcohol and a plurality of porogens.

12. The wafer cleaning brush according to claim 9, wherein the nano-size pores have a diameter of less than 1 um.

13. The wafer cleaning brush according to claim 12, wherein the micro-size pores have a diameter greater than 1 um.

14. A method of forming a cleaning pad, comprising:

mixing a synthetic polymer with a synthetic pore forming agent and an aldehyde to form a mixture, the synthetic pore forming agent being selected from a group of bovine serum albumin, polyethyleneglycol, polyvinyl pyrrolidone and ethyl acetate; and

curing the mixture to form a porous polymeric material.

15. The method according to claim 14, wherein the synthetic polymer is a polyvinyl alcohol.

16. The method according to claim 14, wherein the synthetic pore forming agent is selected from a group of the bovine serum albumin and the polyethyleneglycol and the method further comprises:

prior to the mixing of the synthetic polymer, dissolving the synthetic pore forming agent in a body of water to form a solution and wherein the mixing of the synthetic polymer includes mixing the synthetic polymer with the aldehyde and the solution having the synthetic pore forming agent.

17. The method according to claim 14, wherein the aldehyde is a formaldehyde.

18. A method of forming a cleaning pad, comprising:

mixing a polymer solution with a phosphoric acid and a zinc chloride to form a mixture; and

removing the zinc chloride from the mixture to form a porous polymeric material.

19. The method according to claim 18, wherein the polymer solution includes a polyvinyl alcohol.

20. The method according to claim 18, further comprising forming the polymer solution by dissolving a polymer into a body of water.

21. The method according to claim 20, wherein the forming of the polymer solution includes dissolving the polymer in a powdered form into the body of water by stirring the polymer solution and heating the polymer solution.

22. The method according to claim 21, further comprising after the heating of the polymer solution, cooling the polymer solution and, after cooling the polymer solution, adding a H₃PO₄ compound to the polymer solution.

23. The method according to claim 18, further comprising:

stabilizing the mixture in an air atmosphere.

24. The method according to claim 23, further comprising:

after stabilizing the mixture to in the air atmosphere, heating the mixture in a nitrogen atmosphere.

25. The method according to claim 18, wherein the removing of the zinc chloride includes washing with a deionized water and a hydrochloric acid.

26. A method for cleaning a semiconductor wafer, comprising:

providing a scrubber having a wafer mounted therein and including at least one cleaning brush rotatably mounted adjacent to the wafer;

the cleaning brush including;

a core;

a plurality of spaced-apart nodules disposed to protrude from the core;

each of the nodules having a first portion proximately located relative to the core and a second portion distally located relative to the core;

the first portion including a plurality of micro-size pores;

the second portion including a plurality of nano-size pores; and

scrubbing the wafer by rotatably engaging the wafer with the at least one cleaning brush.

27. The method according to claim 26, wherein each of the nodules include a protrusion of a first porous polymeric material having the plurality of micro-size pores and a layer of a second porous polymeric material having the plurality of nano-size pores coated over a part of the protrusion to form the second portion, with the first portion being an exposed part of the protrusion not coated by the layer.

28. The method according to claim 26, wherein the first porous polymeric material is formed from a first mixture of a polyvinyl alcohol and a porous forming agent;

and the second porous polymeric material is formed from a second mixture of the polyvinyl alcohol and a plurality of porogens.

29. The method according to claim 26, wherein the nano-size pores have a diameter of less than 1 um.

30. The method according to claim 26, wherein the micro-size pores have a diameter of greater than 1 um.