Tetra-organic ammonium fluoride and HF in supercritical fluid for photoresist and residue removal

• US 20040177867A1
• Filed: 05/20/2003
• Published: 09/16/2004
• Est. Priority Date: 12/16/2002
• Status: Abandoned Application

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Supercritical Systems, Inc.
• Inventors: Schilling, Paul E.
• Application Number:
  US10/442,557
• Publication Number:
  US 20040177867A1
• Time in Patent Office: Days
• US Class Current: 134/26
• CPC Class Codes: B08B 7/0021 by liquid gases or supercritical fluids
• CPC Class Codes: G03F 7/427 using plasma means only
• CPC Class Codes: H01L 21/31133 by chemical means
• CPC Class Codes: H01L 21/67028 for cleaning followed by drying, rinsing, stripping, blasting or the like

Abstract

A method of removing a material from an oxide surface of a substrate, where the material is selected from the group consisting of photoresist, photoresist residue, etch residue, and a combination thereof, comprises first and second steps. The first step comprises maintaining a supercritical fluid, a carrier solvent, a tetra-organic ammonium fluoride, and HF in contact with the substrate until the material separates from the oxide surface, thereby forming separated material. The second step comprises removing the separated material from the vicinity of the substrate.

Claims

1. A method of processing a substrate comprising the steps of:

a. maintaining a supercritical fluid, a carrier solvent, a tetra-organic ammonium fluoride, and HF in contact with the substrate, the substrate comprising an oxide surface which supports a material selected from the group consisting of photoresist, photoresist residue, etch residue, and a combination thereof, the supercritical fluid, the carrier solvent, and the quaternary ammonium fluoride maintained in contact with the substrate until the material separates from the oxide surface, thereby forming separated material; and

b. removing the separated material from the vicinity of the substrate.

2. The method of claim 1 wherein the supercritical fluid comprises supercritical carbon dioxide.

3. The method of claim 1 wherein the carrier solvent is selected from the group consisting N,N-dimethylacetamide (DMAC), gamma-butyrolacetone (BLO), dimethyl sufloxide (DMSO), diethyl carbonate (DEC), propylene carbonate (PC), ethylene carbonate (EC), dimethyl formamide (DMF), propylene, butylene carbonate (PBC), N-methylpyrrolidone (NMP), pyrrolidones, heterocyclic solvents, acetic acid, and a mixture thereof.

4. The method of claim 3 wherein the carrier solvent comprises the DMAC.

5. The method of claim 1 wherein the tetra-organic ammonium fluoride comprises

6. The method of claim 5 wherein the R₁, the R₂, the R₃, and the R₄ are selected from the group consisting of butyl, methyl, ethyl, alkyl, fluoroalkyl, branched alkyl, alkylchloride, alkylbromide, and a combination thereof.

7. The method of claim 6 wherein the R₁, the R₂, the R₃, and the R₄ are selected from the group consisting of the butyl, the methyl, the ethyl, and a combination thereof.

8. The method of claim 7 wherein the R₁, the R₂, the R₃, and the R₄ are selected from the group consisting of the butyl, the methyl, and a combination thereof.

9. The method of claim 8 wherein the R₁ the R₂, the R₃, and the R₄ are the butyl.

10. The method of claim 1 further comprising the step of introducing the HF to the supercritical fluid as HF acid.

11. The method of claim 1 wherein the oxide comprises silicon dioxide.

12. The method of claim 1 wherein the oxide comprises aluminum oxide.

13. The method of claim 1 wherein the oxide comprises a low dielectric constant oxide.

14. The method of claim 13 wherein the low dielectric constant oxide comprises a carbon containing oxide material.

15. The method of claim 14 wherein the low dielectric constant material comprises a C—

SiO₂ material.

16. The method of claim 13 wherein the low dielectric constant oxide comprises a porous oxide material.

17. The method of claim 16 wherein the low dielectric constant material comprises a porous SiO₂ material.

18. The method of claim 1 wherein the step of removing the separated material from the vicinity of the substrate comprises flowing supercritical fluid over the substrate.

19. The method of claim 1 further comprising the step of rinsing the substrate in the supercritical carbon dioxide and a rinse agent.

20. The method of claim 19 wherein the rinse agent comprises water.

21. The method of claim 19 wherein the rinse agent comprises alcohol.

22. The method of claim 21 wherein the alcohol comprises ethanol.

23. The method of claim 19 wherein the rinse agent comprises acetone.

24. A method of removing a material from an oxide surface, the material selected from the group consisting of photoresist, photoresist residue, etch residue, and a combination thereof, the method comprising the steps of:

a. maintaining a supercritical fluid, a carrier solvent, a tetra-alkyl ammonium fluoride, and HF in contact with the oxide surface until the material separates from the oxide surface, thereby forming separated material; and

b. removing the separated material from the vicinity of the substrate.

25. A method of removing a material from an oxide surface, the material selected from the group consisting of photoresist, photoresist residue, etch residue, and a combination thereof, the method comprising the steps of:

a. maintaining a supercritical fluid, a carrier solvent, a tetra-butyl ammonium fluoride, and HF in contact with the oxide surface until the material separates from the oxide surface, thereby forming separated material; and

b. removing the separated material from the vicinity of the substrate.