Method of repairing damaged film having low dielectric constant, semiconductor device fabricating system and storage medium

• US 7,556,970 B2
• Filed: 03/26/2007
• Issued: 07/07/2009
• Est. Priority Date: 03/27/2006
• Status: Active Grant

• Current Assignee: Nagoya University, Tokyo Electron Limited
• Original Assignee: Nagoya University, Tokyo Electron Limited
• Inventors: Kubota, Kazuhiro, Hori, Masaru
• Primary Examiner(s): Lindsay, Jr.; Walter L
• Assistant Examiner(s): Lee; Cheung
• Application Number:
  US11/727,392
• Publication Number:
  US 20070232076A1
• Time in Patent Office: 834 Days
• Field of Search: 438/12, 438/42, 438/513, 438/707, 438/709, 438/726, 257/E21.191
• US Class Current: 438/4
• CPC Class Codes: H01L 21/3105 After-treatment
• CPC Class Codes: H01L 21/31116 by dry-etching
• CPC Class Codes: H01L 21/31138 by dry-etching
• CPC Class Codes: H01L 21/76814 post-treatment or after-treatment, e.g. cleaning or removal of oxides on underlying conductors

Abstract

A damaged layer repairing method repairs a damaged layer formed in a surface of a SiOCH film having a low dielectric constant film, containing silicon, carbon, oxygen and hydrogen and formed on a substrate through the elimination of carbon atoms by the decarbonizing effect of plasmas used in an etching process and an ashing process. CH₃ radicals are produced through the thermal decomposition of C₈H₁₈O₂ gas represented by a structural formula: (CH₃)₃COOH(CH₃)₃. CH₃ radicals are brought into contact with the damaged layer in the SiOCH film and are made to bond to the damaged layer to repair the damaged layer.

Claims

1. A damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film, said damaged layer repairing method comprising:

a CH₃ radical producing process for producing CH₃ radicals by supplying energy to a CH₃ radical source gas; and

a repairing process for repairing a damaged layer, from which carbon atoms have been eliminated, formed in a low-dielectric-constant film containing silicon, carbon, oxygen and hydrogen by supplying the CH₃ radicals in the low-dielectric-constant film and bonding the CH₃ radicals to the damaged layer.

2. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 1, wherein the CH₃ radical producing process produces CH₃ radicals through the thermal decomposition of the CH₃ radical source gas.

3. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 2, wherein the damaged layer is formed by a damaged layer formable process in which the low-dielectric-constant film is exposed to a plasma.

4. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 3, wherein the damaged layer formable process in which the low-dielectric-constant film is exposed to a plasma is an etching process for forming a recess in the low-dielectric-constant film and/or an ashing process for ashing an organic resist film formed on the low-dielectric-constant film.

5. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 2, wherein a workpiece on which the low-dielectric-constant film is formed is held in a vacuum atmosphere throughout a damaged layer formable process in which a damaged layer is formed in the low-dielectric-constant film and the repairing process.

6. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 2, wherein the damaged layer formable process and the repairing process are carried out in a single processing vessel.

7. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 2, wherein the CH₃ radical source gas is any one of gases of di-t-alkyl peroxide ((CH₃)₃COOC(CH₃)₃), methane (CH₄), azomethane ((CH₃)₂N₂ and (CH₃)₃N), 2,2′

-azobis isobutylnitrile ((CH₃)₂C(CN)N═

N(CN)C(CH₃)₂), dimethylamine ((CH₃)₂NH) and neopentane (C(CH₃)₄).

8. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 1, wherein the damaged layer is formed by a damaged layer formable process in which the low-dielectric-constant film is exposed to a plasma.

9. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 8, wherein the damaged layer formable process in which the low-dielectric-constant film is exposed to a plasma is an etching process for forming a recess in the low-dielectric-constant film and/or an ashing process for ashing an organic resist film formed on the low-dielectric-constant film.

10. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 1, wherein a workpiece on which the low-dielectric-constant film is formed is held in a vacuum atmosphere throughout a damaged layer formable process in which a damaged layer is formed in the low-dielectric-constant film and the repairing process.

11. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 1, wherein the damaged layer formable process and the repairing process are carried out in a single processing vessel.

12. The damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 1, wherein the CH₃ radical source gas is any one of gases of di-t-alkyl peroxide ((CH₃)₃COOC(CH₃)₃), methane (CH₄), azomethane ((CH₃)₂N₂ and (CH₃)₃N), 2,2′

-azobis isobutylnitrile ((CH₃)₂C(CN)N═

N(CN)C(CH₃)₂), dimethylamine ((CH₃)₂NH) and neopentane (C(CH₃)₄).

13. A storage medium storing a computer program for controlling a repairing system for repairing a damaged layer, formed in a low-dielectric-constant film containing silicon, carbon, oxygen and hydrogen, through elimination of carbon atoms from a surface layer of the low-dielectric-constant film;

wherein the computer program includes instructions to be executed to accomplish the steps of the damaged layer repairing method of repairing a damaged layer in a low-dielectric-constant film according to claim 1.