Polishing assembly with a window

• US 7,255,629 B2
• Filed: 09/15/2006
• Issued: 08/14/2007
• Est. Priority Date: 03/28/1995
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Birang, Manoocher, Gleason, Allan, Guthrie, William L.
• Primary Examiner(s): Wilson; Lee D.
• Application Number:
  US11/532,498
• Publication Number:
  US 20070021037A1
• Time in Patent Office: 333 Days
• Field of Search: 451/6, 451 7- 10, 451/5, 451285-289, 451/41, 451/28, 451/526, 451/539
• US Class Current: 451/6
• CPC Class Codes: B24B 37/013 Devices or means for detecting lapping completion
• CPC Class Codes: B24B 37/205 provided with a window for inspecting the surface of the work being lapped
• CPC Class Codes: B24B 47/12 by mechanical gearing or electric power B24B47/16 takes precedence
• CPC Class Codes: B24B 49/04 involving measurement of the workpiece at the place of grinding during grinding operation
• CPC Class Codes: B24B 49/12 involving optical means
• CPC Class Codes: B24B 51/00 Arrangements for automatic control of a series of individual steps in grinding a workpiece if applicable to other machine tools, G05B takes precedence
• CPC Class Codes: B24D 18/00 Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
• CPC Class Codes: G01B 11/06 for measuring thickness ; e.g. of sheet material thickness measurement by thermal means G01B21/085
• CPC Class Codes: G01B 11/0683 measurement during deposition or removal of the layer

Abstract

The polishing pad for a chemical mechanical polishing apparatus, and a method of making the same. The polishing pad has a covering layer with a polishing surface and a backing layer which is adjacent to the platen. A first opening in the covering layer with a first cross-sectional area and a second opening in the backing layer with a second, different cross-sectional area form an aperture through the polishing pad. A substantially transparent polyurethane plug is positioned in the aperture, and an adhesive material fixes the plug in the aperture.

Claims

1. A polishing assembly for a chemical mechanical polishing apparatus, comprising:

a platen;

a polishing pad with a polishing surface supported on the platen, the polishing pad having an aperture therethrough; and

a solid, substantially transparent window spanning the aperture, wherein a portion of the polishing pad extends laterally over a portion of the window.

2. The polishing assembly of claim 1, wherein the window is secured to the polishing pad by an adhesive.

3. The polishing assembly of claim 1, wherein a top surface of the window is substantially flush with the polishing surface.

4. The polishing assembly of claim 1, wherein the polishing pad includes a polishing layer.

5. The polishing assembly of claim 4, wherein the window extends vertically at least from the polishing surface to a bottom surface of the polishing layer.

6. The polishing assembly of claim 4, wherein the window is secured to the polishing layer.

7. The polishing assembly of claim 6, wherein the window is secured to the polishing layer by an adhesive.

8. The polishing assembly of claim 7, wherein the window is secured to a bottom surface of the polishing layer by the adhesive.

9. The polishing assembly of claim 4, wherein the polishing pad includes a backing layer below the polishing layer.

10. The polishing assembly of claim 6, wherein a portion of the polishing layer projects laterally past the backing layer, and the window is secured to a bottom surface of the portion of the polishing layer.

11. The polishing assembly of claim 1, wherein the platen includes an aperture aligned with the aperture in the polishing pad.

12. The polishing assembly of claim 11, further comprising an optical monitoring system configured to direct a light beam through the aperture in the platen and the aperture in the polishing pad to a substrate and receive a reflected light beam from the substrate through the aperture in the polishing pad and the aperture in the platen.

13. The polishing assembly of claim 12, wherein the platen is rotatable.

14. The polishing assembly of claim 1, wherein the window is rectangular.

15. The polishing assembly of claim 1, wherein the window comprises polyurethane.