Method for preventing metal extrusion in a semiconductor structure.

• US 20040058531A1
• Filed: 08/08/2002
• Published: 03/25/2004
• Est. Priority Date: 08/08/2002
• Status: Abandoned Application

• Current Assignee: United Microelectronics Corporation
• Original Assignee: United Microelectronics Corporation
• Inventors: Hsieh, Yen-Wu, Lee, Shih-Lung, Wu, Ber, Wei, Wen-Shan
• Application Number:
  US10/214,145
• Publication Number:
  US 20040058531A1
• Time in Patent Office: Days
• US Class Current: 438/689
• CPC Class Codes: H01L 21/76802 by forming openings in dielectrics
• CPC Class Codes: H01L 21/76805 the opening being a via or contact hole penetrating the underlying conductor
• CPC Class Codes: H01L 21/76838 characterised by the formation and the after-treatment of the conductors etching for patterning the conductors H01L21/3213

Abstract

A method for preventing metal extrusion in a semiconductor structure is disclosed in this present invention. The point of this invention is that the first metal is suffered to a thermal process before the fabrication of a conformal glue layer into a via onto the first metal layer, and thus the first metal layer will not be extruded by thermal effect any more during the following processes. Therefore, this invention can provide a more efficient method for preventing metal extrusion in a semiconductor structure, and the phenomenon of the raising resistance caused by the metal extrusion can be avoided thereby.

Claims

1. A method for preventing metal extrusion, comprising:

providing a first metal layer;

forming a dielectric layer onto said first metal layer;

etching said dielectric layer to form a via onto said first metal layer;

performing a thermal process; and

depositing a conformal glue layer into said via.

2. The method according to claim 1, further comprises forming a anti-reflection coating layer onto said first metal layer before the step for forming said dielectric layer.

3. The method according to claim 2, wherein said via is through said dielectric layer and said anti-reflection coating layer.

4. The method according to claim 1, wherein said thermal process is performed at a temperature higher than the temperature during said step for providing said first metal layer.

5. The method according to claim 1, wherein said thermal process is performed at a temperature equal to the highest temperature during a plurality of process following the step for etching said dielectric layer.

6. The method according to claim 1, wherein said thermal process is performed at a temperature higher than the highest temperature during a plurality of process following the step for etching said dielectric layer.

7. The method according to claim 1, further comprises filling said via with a secondary metal layer.

8. A method for preventing metal extrusion in a semiconductor structure, comprising:

providing a first metal layer with an anti-reflection coating layer thereon;

forming a dielectric layer onto said anti-reflection coating layer;

etching said dielectric layer and said anti-reflection coating layer to form a via exposing said first metal layer;

performing a thermal process;

depositing a conformal glue layer into said via; and

filling said via with a secondary metal layer.

9. The method according to claim 8, wherein said thermal process is performed at a temperature higher than the temperature of said step for providing said first metal layer.

10. The method according to claim 8, wherein said thermal process is performed at a temperature equal to the highest temperature during a plurality of process following the step for etching said dielectric layer and said anti-reflection coating layer.

11. The method according to claim 8, wherein said thermal process is performed at a temperature higher than the highest temperature during a plurality of process following the step for etching said dielectric layer and said anti-reflection coating layer.

12. The method according to claim 8, wherein said first metal layer is aluminum.

13. The method according to claim 8, wherein said anti-reflection coating layer comprises a Ti layer.

14. The method according to claim 8, wherein said anti-reflection coating layer comprises a TiN layer.

15. The method according to claim 8, wherein said secondary metal layer is tungsten.

16. A method for preventing metal extrusion in a semiconductor structure, comprising:

providing an aluminum layer on a substrate;

forming an anti-reflection coating layer onto said aluminum layer;

forming a dielectric layer onto said substrate and said anti-reflection coating layer;

etching said dielectric layer and said anti-reflection coating layer to form a via exposing said aluminum layer;

performing a thermal process;

depositing a conformal glue layer into said via; and

filling said via with a tungsten layer.

17. The method according to claim 16, wherein said thermal process is performed at a temperature higher than the temperature of said step for providing said aluminum layer.

18. The method according to claim 16, wherein said thermal process is performed at a temperature equal to the highest temperature during a plurality of process following the step for etching said dielectric layer and said anti-reflection coating layer.

19. The method according to claim 16, wherein said thermal process is performed at a temperature higher than the highest temperature during a plurality of process following the step for etching said dielectric layer and said anti-reflection coating layer.

20. The method according to claim 16, wherein said glue layer comprises a Ti layer.

21. The method according to claim 16, wherein said glue layer comprises a TiN layer.