US 12,330,266 B2
Polishing apparatus with thickness measuring unit
Kazuma Sekiya, Tokyo (JP); and Keiji Nomaru, Tokyo (JP)
Assigned to DISCO CORPORATION, Tokyo (JP)
Filed by DISCO CORPORATION, Tokyo (JP)
Filed on Nov. 16, 2022, as Appl. No. 18/055,941.
Claims priority of application No. 2021-187197 (JP), filed on Nov. 17, 2021.
Prior Publication US 2023/0150086 A1, May 18, 2023
Int. Cl. B24B 49/12 (2006.01); B24B 37/013 (2012.01); B24B 37/04 (2012.01); B24B 37/20 (2012.01); H01L 21/67 (2006.01)
CPC B24B 49/12 (2013.01) [B24B 37/013 (2013.01); B24B 37/042 (2013.01); B24B 37/20 (2013.01); H01L 21/67253 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A polishing apparatus comprising:
a chuck table that has a holding surface and is rotatable and is moveable in a direction parallel to the holding surface;
a polishing unit that rotatably supports a polishing pad for polishing a wafer comprising grinding marks held on the holding surface of the chuck table and that has a spindle formed with a through-hole extending from one end of the spindle to the other end of the spindle in an axis of the spindle;
a vertical feeding mechanism that relatively puts the polishing unit into processing feeding in a vertical direction to the holding surface of the chuck table;
a thickness measuring unit that is disposed at a first end of the through-hole of the spindle and that measures a thickness of the wafer during or after the wafer is polished by the polishing pad; and
a controller,
wherein the controller obtains information regarding the thickness of the wafer measured by the thickness measuring unit at a plurality of positions defined by a variation in a distance between a rotational center of the rotating wafer held on the chuck table and a center of a second end of the through-hole facing the wafer and by variation in a rotational angle of the chuck table, and forms mapping data regarding the thickness of the wafer.