Polishing system with platen for substrate edge control

Patent metadata

Field	Value
Publication number	US-11890717-B2
Application number	US-201916716213-A
Country	US
Kind code	B2
Filing date	Dec 16, 2019
Priority date	Dec 26, 2018
Publication date	Feb 6, 2024
Grant date	Feb 6, 2024

Abstract

A polishing system includes a platen having a top surface to support a main polishing pad. The platen is rotatable about an axis of rotation that passes through approximately the center of the platen. An annular flange projects radially outward from the platen to support an outer polishing pad. The annular flange has an inner edge secured to and rotatable with the platen and vertically fixed relative to the top surface of the platen. The annular flange is vertically deflectable such that an outer edge of the annular flange is vertically moveable relative to the inner edge. An actuator applies pressure to an underside of the annular flange in an angularly limited region, and a carrier head holds a substrate in contact with the polishing pad and is movable to selectively position a portion of the substrate over the outer polishing pad.

First claim

What is claimed is:

1. A polishing system, comprising:
a platen having a top surface to support a main polishing pad, the platen rotatable about an axis of rotation that passes through approximately a center of the platen;
an annular flange projecting radially outward from the platen to support an outer polishing pad, the annular flange being a unitary body having an inner edge secured to and rotatable with the platen and vertically fixed relative to the top surface of the platen, the annular flange being deformable and vertically deflectable such that an outer edge of the annular flange is vertically movable relative to the inner edge;
an actuator configured to apply pressure to an underside of the annular flange in an angularly limited region such that the angularly limited region of the annular flange and an angularly limited portion of the outer polishing pad are lifted relative to the platen, an undeformed portion of annular flange, and main polishing pad; and
a carrier head to hold a substrate in contact with the main polishing pad and movable to selectively position a portion of the substrate over the angularly limited portion of the outer polishing pad.

2. The polishing system of claim 1 , comprising the outer polishing pad.

3. The polishing system of claim 2 , wherein the outer polishing pad is angularly segmented by channels.

4. The polishing system of claim 2 , wherein the outer polishing pad has a polishing surface separated from the main polishing pad by a gap.

5. The polishing system of claim 4 , wherein the polishing surface has a polygonal cross-section perimeter.

6. The polishing system of claim 4 , wherein the polishing surface is annular.

7. The polishing system of claim 2 , wherein the outer polishing pad has a conduit for polishing residue to drain.

8. The polishing system of claim 2 , further comprising the main polishing pad.

9. The polishing system of claim 8 , wherein the outer polishing pad is harder than the main polishing pad.

10. The polishing system of claim 8 , wherein the outer polishing pad is softer than the main polishing pad.

11. The polishing system of claim 8 , wherein the main polishing pad and outer polishing pad are composed of the same material.

12. The polishing system of claim 1 , wherein the platen, or the annular flange, or both, comprise a conduit for polishing residue to drain from a gap between a polishing surface of the outer polishing pad and a polishing surface of the main polishing pad.

13. The polishing system of claim 1 , further comprising:
an aperture in the top surface of the platen that overlaps the center of the platen;
a second annular flange projecting radially inward from the platen into the aperture to support an inner polishing pad, the second annular flange having an outer edge secured to and rotatable with the platen and vertically fixed relative to the top surface of the platen, the second annular flange being vertically deflectable such that an inner edge of the second annular flange is vertically movable relative to the outer edge; and
a second actuator configured to apply pressure to an underside of the second annular flange in an angularly limited region such that an angularly limited section of the second annular flange and an angularly limited portion of the inner polishing pad are lifted relative to the platen, an undeformed portion of the annular flange, and main polishing pad.

14. The polishing system of claim 13 , wherein the aperture comprises a recess extending partially but not entirely through the platen.

15. The polishing system of claim 14 , comprising a conduit through the platen for liquid polishing residue to drain from the recess.

16. The polishing system of claim 13 , wherein the carrier head is movable to selectively position a portion of the substrate over the inner polishing pad.

17. The polishing system of claim 1 , wherein an upper surface of the annular flange is coplanar to a top surface of the platen.

18. The polishing system of claim 1 , wherein the actuator includes an arm having a wheel in contact with the underside of the annular flange.

19. The polishing system of claim 18 , wherein the wheel is in static contact with the underside of the annular flange.

20. A polishing system, comprising:
an annular platen having a top surface to support a main polishing pad, the annular platen having an aperture in a top surface of the annular platen that overlaps a center of the annular platen, the annular platen rotatable about an axis of rotation that passes through approximately the center of the annular platen;
an annular flange projecting radially inward from the annular platen into the aperture to support an inner polishing pad, the annular flange being a unitary body having an outer edge secured to and rotatable with the annular platen and vertically fixed relative to the top surface of the annular platen, the annular flange being vertically deflectable such that an inner edge of the annular flange being deformable and vertically movable relative to the outer edge of the annular flange;
an actuator configured to apply pressure to an underside of the annular flange in an angularly limited region such that the angularly limited region of the annular flange and an angularly limited portion of the inner polishing pad are lifted relative to the annular platen, an undeformed portion of the annular flange, and main polishing pad; and
a carrier head to hold a substrate in contact with the main polishing pad and movable to selectively position a portion of the substrate over the angularly limited portion of the inner polishing pad.

Assignees

• Applied Materials Inc

Inventors

• Gurusamy Jay
• Zuniga Steven M
• Oh Jeonghoon

Classifications

• B24B37/013 Primary

  Devices or means for detecting lapping completion · CPC title

• B24B37/14

  characterised by the composition or properties of the plate materials · CPC title

• B24B37/26

  characterised by the shape of the lapping pad surface, e.g. grooved · CPC title

• B24B37/27

  Work carriers · CPC title