Cleaning method and solution for cleaning a wafer in a single wafer process

• US 7,449,127 B2
• Filed: 06/03/2005
• Issued: 11/11/2008
• Est. Priority Date: 06/26/2000
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Verhaverbeke, Steven, Truman, J. Kelly
• Primary Examiner(s): Tran; Binh X
• Application Number:
  US11/145,304
• Publication Number:
  US 20050227888A1
• Time in Patent Office: 1,257 Days
• Field of Search: 252/79.1, 252/79.4, 438/745, 134/1.3, 134/1.2
• US Class Current: 252/79.1
• CPC Class Codes: B08B 3/08 the liquid having chemical or dissolving effect substances used, see the relevant classes
• CPC Class Codes: C11D 1/29 Sulfates of polyoxyalkylene ethers
• CPC Class Codes: C11D 1/72 Ethers of polyoxyalkylene glycols
• CPC Class Codes: C11D 2111/22 Electronic devices, e.g. PCBs or semiconductors
• CPC Class Codes: C11D 3/044 Hydroxides or bases
• CPC Class Codes: C11D 3/32 Amides; Substituted amides
• CPC Class Codes: C11D 3/33 Amino carboxylic acids
• CPC Class Codes: C11D 3/3947 Liquid compositions
• CPC Class Codes: C11D 7/06 Hydroxides
• CPC Class Codes: C11D 7/265 Carboxylic acids or salts thereof
• CPC Class Codes: C23G 5/00 Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents
• CPC Class Codes: H01L 21/02052 Wet cleaning only H01L21/02085 takes precedence
• CPC Class Codes: H01L 21/67051 using mainly spraying means, e.g. nozzles
• CPC Class Codes: Y10S 261/07 Carbonators

Abstract

The present invention is a novel cleaning method and a solution for use in a single wafer cleaning process. According to the present invention the cleaning solution comprises ammonium hydroxide (NH₄OH), hydrogen peroxide (H₂O₂), water (H₂O) and a chelating agent. In an embodiment of the present invention the cleaning solution also contains a surfactant. And still yet another embodiment of the present invention the cleaning solution also comprises a dissolved gas such as H₂. In a particular embodiment of the present invention, this solution is used by spraying or dispensing it on a spinning wafer.

Claims

1. A cleaning solution formed from a mixture comprising:

NH₄OH;

H₂O₂;

H₂O;

a chelating agent selected from the group consisting of N,N′

-Bis(2-hydroxyphenyl)ethylenediiminodiacetic acid (HPED) and molybdic acid; and

a surfactant.

2. The cleaning solution of claim 1 wherein said NH₄OH, H₂O₂, and H₂O have a mixing ratio of between 5/1/1 and 1000/1/1.

3. The cleaning solution of claim 1 wherein said NH₄OH is from a solution of between 28-29% w/w of NH₃ to water.

4. The cleaning solution of claim 1 wherein said H₂O₂ is from a solution of between 31-32% w/w of H₂O₂ to water.

5. The cleaning solution of claim 1 wherein said chelating agent has an equilibrium constant (K) greater than 10¹⁵ for aluminum.

6. The cleaning solution of claim 1 wherein said chelating agent has an equilibrium constant (K) greater than 10²⁰ for aluminum.

7. The cleaning solution of claim 1 wherein said chelating agent is N,N′

-Bis(2-hydroxyphenyl)ethylenediiminodiacetic acid (HPED).

8. The cleaning solution of claim 1 wherein said chelating agent has a concentration in said solution between 0.001 mg/l and 300 mg/l.

9. The cleaning solution of claim 1 wherein said chelating agent has a concentration in said solution of between 0.01 mg/l and 3 mg/l.

10. The cleaning solution of claim 1 wherein said chelating agent has a concentration in said solution of between 1 -400 ppm.

11. The cleaning solution of claim 1 wherein said surfactant is non-ionic.

12. The cleaning solution of claim 1 wherein said chelating agent is molybdic acid.

13. The cleaning solution of claim 1 wherein said surfactant is anionic.

14. The cleaning solution of claim 13 wherein said surfactant is 05 volume percent of said cleaning solution.

15. A cleaning solution comprising:

NH₄OH; and

N,N′

-Bis(2-hydroxyphenyl)ethylenediiminodiacetic acid (HPED).

16. The cleaning solution of claim 15 further comprising H₂O₂, H₂O, and a surfactant.

17. The cleaning solution of claim 15 wherein said chelating agent has a concentration in said solution between 0.001 mg/l and 300 mg/l.

18. The cleaning solution of claim 15 wherein said chelating agent has a concentration in said solution of between 1-400 ppm .

19. A cleaning solution comprising:

H₂O₂;

NH₄OH; and

molybdic acid.

20. The cleaning solution of claim 19, further comprising a surfactant.

21. The cleaning solution of claim 19 wherein said molybdic acid has a concentration in said solution between 0.001 mg/l and 300 mg/l.

22. The cleaning solution of claim 19 wherein said molybdic acid has a concentration in said solution of between 1-1400 ppm.