Acoustic emission monitoring and endpoint for chemical mechanical polishing

Patent metadata

Field	Value
Publication number	US-10478937-B2
Application number	US-201514639859-A
Country	US
Kind code	B2
Filing date	Mar 5, 2015
Priority date	Mar 5, 2015
Publication date	Nov 19, 2019
Grant date	Nov 19, 2019

Abstract

A chemical mechanical polishing apparatus includes a platen to support a polishing pad, and an in-situ acoustic emission monitoring system including an acoustic emission sensor supported by the platen, a waveguide configured to extending through at least a portion of the polishing pad, and a processor to receive a signal from the acoustic emission sensor. The in-situ acoustic emission monitoring system is configured to detect acoustic events caused by deformation of the substrate and transmitted through the waveguide, and the processor is configured to determine a polishing endpoint based on the signal.

First claim

What is claimed is:

1. A chemical mechanical polishing apparatus, comprising:
a platen to support a polishing pad; and
an in-situ acoustic monitoring system to generate a signal, the in-situ acoustic monitoring system including an acoustic emission sensor supported by the platen and an acoustic waveguide positioned to extend through the polishing pad such that the acoustic waveguide has a first end coupled to the acoustic emission sensor and a second end in a groove in the polishing pad so that the acoustic emission sensor receives acoustic signals that propagate through slurry in the groove in the polishing pad.

2. The apparatus of claim 1 , comprising the polishing pad, the polishing pad having a polishing layer and a plurality of slurry-transport grooves in a polishing surface of the polishing layer, the groove being one of the plurality of slurry-transport grooves.

3. The apparatus of claim 2 , wherein a tip of the waveguide is positioned below the polishing surface.

4. The apparatus of claim 2 , wherein the polishing pad comprises a backing layer between the polishing layer and the platen.

5. The apparatus of claim 4 , wherein backing layer has an aperture therethrough and the waveguide extends through the aperture.

6. The apparatus of claim 2 , wherein the waveguide punctures the polishing layer in a substantially sealed manner.

7. The apparatus of claim 1 , wherein the in-situ acoustic monitoring system comprises a plurality of parallel waveguides.

8. The apparatus of claim 1 , wherein a position of the waveguide is vertically adjustable.

9. The apparatus of claim 1 , wherein the waveguide comprises an elongated body extending substantially perpendicular to a top surface of the platen.

10. The apparatus of claim 9 , wherein the waveguide comprises needle-shaped body.

Assignees

• Applied Materials Inc

Inventors

• Tang Jianshe
• Ishikawa David Masayuki
• Cherian Benjamin
• Oh Jeonghoon
• Osterheld Thomas H

Classifications

• B24B37/013 Primary

  Devices or means for detecting lapping completion · CPC title

• B24B49/003

  involving acoustic means · CPC title

• B24B37/20

  Lapping pads for working plane surfaces · CPC title

• B24B37/10

  for single side lapping · CPC title

• B24B37/042 Primary

  operating processes therefor · CPC title