Apparatus and method for surface cleaning using plasma

• US 20040194799A1
• Filed: 04/23/2004
• Published: 10/07/2004
• Est. Priority Date: 01/08/2001
• Status: Abandoned Application

• Current Assignee: Gil-Gwang Lee, Jeong-Ho Kim
• Original Assignee: Gil-Gwang Lee, Jeong-Ho Kim
• Inventors: Kim, Jeong-Ho, Lee, Gil-Gwang
• Application Number:
  US10/831,252
• Publication Number:
  US 20040194799A1
• Time in Patent Office: Days
• US Class Current: 134/1.3
• CPC Class Codes: B08B 7/00 Cleaning by methods not provided for in a single other subclass or a single group in this subclass
• CPC Class Codes: H01L 21/02063 the processing being the formation of vias or contact holes
• CPC Class Codes: H01L 21/31116 by dry-etching
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 21/76814 post-treatment or after-treatment, e.g. cleaning or removal of oxides on underlying conductors

Abstract

There is provided a surface cleaning apparatus and method using plasma to remove a native oxide layer, a chemical oxide layer, and a damaged portion from a silicon substrate surface, and contaminants from a metal surface. By absorbing potential in a grounded grid or baffle between a plasma generator and a substrate, only radicals are passed to the substrate, and HF gas is used as a second processing gas. Thus a native oxide layer, a chemical oxide layer, or a damaged portion formed on the silicon substrate during etching a contact hole is removed and the environment of a chamber is maintained constant by introducing a conditioning gas after each wafer process. Therefore, process uniformity is improved.

Claims

1. A surface cleaning method using plasma, for removing a damaged portion and an unwanted oxide layer formed during etching for a contact hole on a silicon substrate having at least one layer including an insulation layer, the method comprising the steps of:

forming a polymer layer on the oxide layer;

removing the polymer layer and the oxide layer by annealing; and

removing the damaged portion of the surface of the silicon substrate.

2. The method of claim 1, the polymer layer formation step comprises the steps of:

forming plasma by introducing a first processing gas containing H2 or N2;

passing only radicals to the silicon substrate by filtering the plasma; and

introducing a second processing gas containing a halogen element.

3. The method of claim 2, wherein the second processing gas is at least one of HF, HCl, BCl3, HBr, and ClF3.

4. The method of claim 1, wherein the polymer layer and the oxide layer are removed by annealing using a UV lamp or IR lamp.

5. The method of claim 2, wherein the polymer layer and the oxide layer are removed by annealing using a UV lamp or IR lamp.

6. The method of claim 1, wherein the polymer layer and the oxide layer are removed by annealing in a heat chamber.

7. The method of claim 2, wherein the polymer layer and the oxide layer are removed by annealing in a heat chamber.

8. The method of claim 1, wherein the damaged portion of the silicon substrate surface is removed using remote plasma formed out of a fluorine (F)-containing gas.

9. The method of claim 8, wherein the fluorine-containing gas is at least one of HF/H2, HF/O2, NF3/O2, SF6/O2, and CF4/O2.

10. The method of claim 1, wherein the damaged portion of the silicon substrate surface is removed using remote plasma formed out of a Cl-containing gas.

11. The method of claim 1, wherein the damaged portion of the silicon substrate surface is removed by annealing in a heat chamber.

12. The method of claim 6, wherein the damaged portion removal step is performed in-situ in the same chamber after removing the polymer layer and the oxide layer.

13. The method of claim 7, wherein the damaged portion removal step is performed in-situ in the same chamber after removing the polymer layer and the oxide layer.

14. A surface cleaning method using plasma for fabrication of an integrated circuit in a surface cleaning apparatus having a chamber that can be maintained in a vacuum state, a substrate mount for mounting a silicon substrate, a first processing gas inlet for introducing a carrier gas for generation and maintenance of plasma, a plasma generator, a filter for passing only radicals to the substrate, and a second processing gas inlet, the method comprising the steps of:

introducing the first processing gas into the chamber;

forming plasma out of the first processing gas in the plasma generator; and

introducing a second processing gas into the chamber.

15. The method of claim 14, wherein the first processing gas contains one of H2 and N2.

16. The method of claim 14, wherein the second processing gas contains a halogen element.

17. The method of claim 14, wherein the second processing gas is at least one of HF, HCl, BCl3, HBr, and ClF3.

18. A surface cleaning method using plasma for fabrication of an integrated circuit in a surface cleaning apparatus having a chamber that can be maintained in a vacuum state, a substrate mount for mounting a silicon substrate, a first processing gas inlet for introducing a carrier gas for generation and maintenance of plasma, a plasma generator, a filter for passing only radicals to the substrate, a second processing gas inlet, and a third processing gas inlet for introducing a third processing gas to maintain the environment of the chamber constant after processing each wafer, the method comprising the steps of:

introducing the first processing gas into the chamber;

forming plasma out of the first processing gas in the plasma generator;

introducing a second processing gas into the chamber; and

introducing the third processing gas into the chamber to maintain the environment of the chamber constant after processing each wafer

19. The method of claim 18, wherein the first processing gas contains one of H2 and N2.

20. The method of claim 18, wherein the second processing gas contains a halogen element.

21. The method of claim 18, wherein the second processing gas is at least one of HF, HCl, BCl3, HBr, and ClF3.

22. The method of claim 18, wherein the third processing gas contains at least of H, F, O and N.

32. The method of claim 19, wherein the third processing gas contains at least one of H, F, O and N.

33. The method of claim 20, wherein the third processing gas contains at least one of H, F, O and N.

34. The method of claim 21, wherein the third processing gas contains at least one of H, F, O and N.

23-31. -31 (cancelled)