Removal of particle contamination on a patterned silicon/silicon dioxide using dense fluid/chemical formulations

• US 20060019850A1
• Filed: 09/12/2005
• Published: 01/26/2006
• Est. Priority Date: 10/31/2002
• Status: Abandoned Application

• Current Assignee: Advanced Technology Materials, Inc. (Entegris Incorporated)
• Original Assignee: Advanced Technology Materials, Inc. (Entegris Incorporated)
• Inventors: Xu, Chongying, Korzenski, Michael B., Baum, Thomas H.
• Application Number:
  US11/224,214
• Publication Number:
  US 20060019850A1
• Time in Patent Office: Days
• US Class Current: 510/175
• CPC Class Codes: B08B 7/0021 by liquid gases or supercritical fluids
• CPC Class Codes: C11D 1/004 Surface-active compounds containing F
• CPC Class Codes: C11D 1/83 Mixtures of non-ionic with anionic compounds
• CPC Class Codes: C11D 11/0047 Electronic devices, e.g. PCBs or semiconductors
• CPC Class Codes: C11D 2111/22 Electronic devices, e.g. PCBs or semiconductors
• CPC Class Codes: C11D 3/042 Acids
• CPC Class Codes: C11D 3/046 Salts
• CPC Class Codes: C11D 3/201 linear
• CPC Class Codes: C11D 3/2034 aromatic
• CPC Class Codes: C11D 3/24 containing halogen C11D3/162, C11D3/164, C11D3/166, C11D3/168 take precedence
• CPC Class Codes: H01L 21/02063 the processing being the formation of vias or contact holes
• CPC Class Codes: H01L 21/02101 only involving supercritical fluids

Abstract

A cleaning composition for cleaning particulate contamination from small dimensions on microelectronic device substrates. The cleaning composition contains dense CO₂ (preferably supercritical CO₂ (SCCO₂)), alcohol, fluoride source, anionic surfactant source, non-ionic surfactant source, and optionally, hydroxyl additive. Such cleaning composition overcomes the intrinsic deficiency of SCCO₂ as a cleaning reagent, viz., the non-polar character of SCCO₂ and its associated inability to solubilize species such as inorganic salts and polar organic compounds that are present in particulate contamination on wafer substrates and that must be removed from the microelectronic device substrate for efficient cleaning. The cleaning composition enables damage-free, residue-free cleaning of substrates having particulate contamination on Si/SiO₂ substrates.

Claims

1. A particle contamination cleaning composition, comprising dense CO₂, at least one alcohol, at least one fluoride source, at least one anionic surfactant, at least one non-ionic surfactant, and optionally, at least one hydroxyl additive, wherein said cleaning composition is suitable for removing particle contamination from a microelectronic device having said particle contamination thereon.

2. The composition of claim 1, wherein the at least one alcohol comprises C₁-C₄ alcohol, and wherein the at least one fluoride source comprises a fluoride-containing compound selected from the group consisting of hydrogen fluoride (HF), amine trihydrogen fluoride compounds of the formula NR₃(HF)₃ wherein each R is independently selected from hydrogen and lower alkyl, hydrogen fluoride-pyridine (pyr-HF), and ammonium fluorides of the formula R₄NF, wherein each R is independently selected from hydrogen and lower alkyl.

3. The composition of claim 1, wherein the at least one alcohol comprises methanol.

4. The composition of claim 1, wherein the at least one fluoride source comprises ammonium fluoride (NH₄F).

5. The composition of claim 1, wherein the at least one hydroxyl additive comprises a species selected from the group consisting of boric acid and 2-fluorophenol.

6. The composition of claim 1, wherein the at least one hydroxyl additive is also at least a part of said fluoride source.

7. The composition of claim 1, wherein said at least one alcohol has a concentration in a range of from about 5 to about 20 wt. %, based on total weight of the composition.

8. The composition of claim 1, wherein the at least one fluoride source has a concentration of from about 0.01 to about 2.0 wt. %, based on the total weight of the cleaning composition.

9. The composition of claim 1, wherein the at least one anionic surfactant is fluorinated.

10. The composition of claim 1, wherein the at least one non-ionic surfactant is fluorinated.

11. The composition of claim 1, comprising ammonium fluoride, at least one fluorinated surfactant and boric acid.

12. The composition of claim 1, comprising ammonium fluoride, a fluorinated anionic surfactant, a fluorinated nonionic surfactant, and boric acid.

13. The composition of claim 11, wherein said ammonium fluoride has a concentration of from about 0.1 to about 5.0 wt. %, based on the total weight of the cleaning composition.

14. A kit comprising, in one or more containers, cleaning composition reagents, wherein the cleaning composition comprises at least one alcohol, at least one fluoride source, at least one anionic surfactant, at least one non-ionic surfactant, and optionally, at least one hydroxyl additive, and wherein the kit is adapted to form a cleaning composition suitable for removing particle contamination from a microelectronic device having said particle contamination thereon.

15. A method of removing particle contamination from a microelectronic device substrate having same thereon, said method comprising contacting the particle contamination with a cleaning composition for sufficient time to at least partially remove said particle contamination from the microelectronic device, wherein the cleaning composition includes dense CO₂, at least one alcohol, at least one fluoride source, at least one anionic surfactant, at least one non-ionic surfactant, and optionally, at least one hydroxyl additive.

16. The method of claim 15, wherein said contacting conditions comprise elevated pressure.

17. The method of claim 16, wherein said elevated pressure comprises pressure in a range of from about 1000 to about 7500 psi.

18. The method of claim 15, wherein said contacting time is in a range of from about 5 to about 30 minutes.

19. The method of claim 15, wherein the at least one alcohol comprises C₁-C₄ alcohol, and wherein the at least one fluoride source comprises a fluoride-containing compound selected from the group consisting of hydrogen fluoride (HF), amine trihydrogen fluoride compounds of the formula NR₃(HF)₃ wherein each R is independently selected from hydrogen and lower alkyl, hydrogen fluoride-pyridine (pyr-HF), and ammonium fluorides of the formula R₄NF, wherein each R is independently selected from hydrogen and lower alkyl.

20. The method of claim 15, wherein said composition comprises SCCO₂, methanol, ammonium fluoride, at least one fluorinated surfactant, and boric acid, wherein methanol is present at a concentration of from about 5 to about 20 wt. %, fluoride is present at a concentration of from about 0.01 to about 5.0 wt. %, and boric acid is present at a concentration of from about 0.01 to about 2.0 wt. %, based on the total weight of the cleaning composition.

21. The method of claim 15, wherein the contacting step comprises a cleaning cycle including

(i) dynamic flow contacting of the cleaning composition with the particle contamination, and

(ii) static soaking contacting of the cleaning composition with the particle contamination.

22. The method of claim 21, wherein said cleaning cycle comprises alternatingly and repetitively carrying out dynamic flow contacting (i) and static soaking contacting (ii) of the particle contamination.

23. The method of claim 22, wherein said cleaning cycle comprises carrying out (i) dynamic flow contacting and (ii) static soaking contacting in sequence, and repeating said sequence three times.

24. The method of claim 15, further comprising the step of washing the substrate at a region at which the particulate contamination has been removed, with a SCCO₂/alcohol wash solution in a first washing step, and with SCCO₂ in a second washing step, to remove residual precipitated chemical additives in said first washing step, and to remove residual precipitated chemical additives and/or residual alcohol in said second washing step.