Acoustic carrier head monitoring

Inventors: Jeonghoon Oh (Saratoga, CA); Jianshe Tang (San Jose, CA); Steven M. Zuniga (Soquel, CA); Brian J. Brown (Palo Alto, CA); Andrew J. Nagengast (Sunnyvale, CA); Derek R. Witty (Fremont, CA); Rushabhkumar Desai (San Jose, CA); Shih-Haur Shen (Sunnyvale, CA); Haosheng Wu (San Jose, CA); Yufei Hu (Fremont, CA)

Assignee: Applied Materials, Inc.

B24B37/005 B24B37/042

View Patent ↗

Loading inventors, assignments & file history…

Monitor This Case

Get email alerts when status or documents change.

Order Certified Copies

Most orders are placed with the USPTO same day — all within 24 business hours.

Order via The Patent Place →

Pre-filled with this patent's details

Quick Facts

Patent No.: US 12708978
App. No.: 18/101,025
Granted: Aug 18, 2026
Kind: B2

External Links

USPTO Patent Center↗ Full Patent PDF↗

Abstract

A chemical mechanical polishing apparatus has a platen to support a polishing pad, a carrier head comprising a rigid housing and configured to hold a surface of a substrate against the polishing pad, a motor to generate relative motion between the platen and the carrier head so as to polish the substrate, an in-situ carrier head monitoring system including a sensor positioned to interact with the housing and to detect vibrational motion of the housing and generate signals based on the detected vibrational motion, and a controller. The controller is configured to generate a value for a carrier head status parameter based on received signals from the in-situ carrier head monitoring system, and change a polishing parameter or generate an alert based on the carrier head status parameter.

Claims (31)

1 . A chemical mechanical polishing apparatus, comprising:

a platen to support a polishing pad;

a carrier head comprising a rigid housing, the carrier head configured to hold a surface of a substrate against the polishing pad;

a motor to generate relative motion between the platen and the carrier head so as to polish the substrate;

an in-situ carrier head monitoring system including a sensor positioned to interact with the housing and to detect vibrational motion of the housing and generate signals based on the detected vibrational motion; and

a controller configured to

generate a value for a carrier head status parameter based on received signals from the in-situ carrier head monitoring system, wherein the carrier head status parameter indicates an impending fault prior to the fault occurring, and

change a polishing parameter or generate an alert based on the carrier head status parameter.

2 . The apparatus of claim 1 , wherein the sensor of the in-situ carrier head monitoring system is mounted to an outer surface of the housing.

3 . The apparatus of claim 2 , wherein the sensor is mounted to a top surface of the housing.

4 . The apparatus of claim 2 , wherein the sensor comprises an accelerometer.

5 . The apparatus of claim 1 , wherein the sensor of the in-situ carrier head monitoring system is spaced from and configured to direct electromagnetic energy to an outer surface of the housing.

6 . The apparatus of claim 5 , wherein the sensor comprises a displacement sensor.

7 . The apparatus of claim 6 , wherein the displacement sensor is configured to monitor vertical displacement of the housing.

8 . The apparatus of claim 6 , wherein the displacement sensor is an optical displacement sensor.

9 . The apparatus of claim 8 , wherein the optical displacement sensor is configured to generate measurements at a frequency in a range from 1 kHz to 100 kHz and to measure displacements in the carrier head at a resolution of less than 1 μm.

10 . The apparatus of claim 8 , wherein the sensor comprises a laser interferometer.

11 . The apparatus of claim 1 , wherein the carrier head comprises a gimbal mechanism, and the in-situ carrier head monitoring system comprises a strain sensor mounted to the gimbal mechanism, and the detected vibrational motion is a detected angular deflection of the housing from a rotational axis of the gimbal mechanism.

12 . The apparatus of claim 11 , wherein the gimbal mechanism is a flexible gimbal mechanism or a ball-in-socket gimbal mechanism.

13 . The apparatus of claim 1 , wherein the controller is further configured to determine a polishing endpoint based on the carrier head status parameter.

14 . The apparatus of claim 1 , wherein the carrier head status parameter comprises a carrier head displacement, a shear force, a carrier head rotation speed, or a carrier head type.

15 . The apparatus of claim 1 , wherein the vibrational motion occurs at a frequency above a frequency threshold.

16 . A method of polishing, comprising:

holding a substrate against a polishing surface of a polishing pad with a carrier head;

generating relative motion between the substrate and polishing pad;

monitoring a vibrational motion of the carrier head with an in-situ carrier head monitoring system to generate a signal based on the motion;

generate a value for a carrier head status parameter based on the signals from the in-situ carrier head monitoring system, wherein the carrier head status parameter indicates an impending fault prior to the fault occurring; and

changing a polishing parameter or generating an alert based on the value generated for the carrier head status parameter.

17 . The method of claim 16 , wherein monitoring the carrier head comprises monitoring an angular deflection of the carrier head with respect to an axis of rotation of the carrier head, and the signal is a strain signal.

18 . The method of claim 16 , wherein monitoring the carrier head comprises monitoring a vertical displacement of the carrier head with respect to the in-situ head monitoring system, and the signal is an optical signal.

19 . The method of claim 16 , wherein monitoring the carrier head comprises monitoring a vibration of the carrier head, and the signal is an acceleration signal.