US 12,447,579 B2
Chemical mechanical polishing vibration measurement using optical sensor
Jeonghoon Oh, Saratoga, CA (US); Thomas H. Osterheld, Mountain View, CA (US); and Steven M. Zuniga, Soquel, CA (US)
Assigned to Applied Materials, Inc., Santa Clara, CA (US)
Filed by Applied Materials, Inc., Santa Clara, CA (US)
Filed on Jul. 5, 2022, as Appl. No. 17/858,011.
Claims priority of provisional application 63/218,887, filed on Jul. 6, 2021.
Prior Publication US 2023/0010759 A1, Jan. 12, 2023
Int. Cl. B24B 49/12 (2006.01); B24B 37/013 (2012.01); B24B 37/04 (2012.01); H01L 21/66 (2006.01); H01L 21/306 (2006.01); H01L 21/3105 (2006.01); H01L 21/321 (2006.01)
CPC B24B 37/013 (2013.01) [B24B 37/042 (2013.01); H01L 22/26 (2013.01); H01L 21/30625 (2013.01); H01L 21/31053 (2013.01); H01L 21/3212 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A chemical mechanical polishing apparatus, comprising:
a platen to support a polishing pad;
a carrier head to hold a substrate against a polishing surface of the polishing pad;
a motor to generate relative motion between the platen and the carrier head so as to polish an overlying layer on the substrate;
an in-situ pad vibration monitoring system including a light source to emit a light beam and a sensor that receives a reflection of the light beam from a reflective surface parallel with a polishing surface of the polishing pad; and
a controller configured to detect exposure of an underlying layer due to the polishing of the substrate based on measurements from the sensor of the in-situ pad vibration monitoring system, the measurements indicative of a vibration of the reflective surface in a direction normal to the polishing surface.