US 11,980,993 B2
Method of grinding workpiece
Yoshikazu Suzuki, Tokyo (JP)
Assigned to DISCO CORPORATION, Tokyo (JP)
Filed by DISCO CORPORATION, Tokyo (JP)
Filed on Mar. 24, 2022, as Appl. No. 17/656,357.
Claims priority of application No. 2021-063374 (JP), filed on Apr. 2, 2021.
Prior Publication US 2022/0314393 A1, Oct. 6, 2022
Int. Cl. B24B 37/27 (2012.01); B24B 7/04 (2006.01); B24B 7/22 (2006.01)
CPC B24B 37/27 (2013.01) [B24B 7/04 (2013.01); B24B 7/228 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method of grinding a plate-shaped workpiece held on a holding surface of a chuck table with a grinding wheel having a plurality of grindstones disposed in an annular array while the chuck table and the grinding wheel are being rotated with the grindstones moving across a rotational axis of the chuck table, the method comprising:
a first grinding step of adjusting a relative tilt of the chuck table and the grinding wheel to a first state in which distances between the grindstones and the holding surface are larger in other positions than a position where the grindstones overlap the rotational axis of the chuck table, and moving the holding surface and the grindstones relatively closer to each other to bring the grindstones into abrasive contact with the workpiece to thereby grind the workpiece;
a grinding stopping step of spacing the grindstones from the workpiece to stop grinding the workpiece, after the first grinding step; and
a second grinding step of adjusting the relative tilt of the chuck table and the grinding wheel to a second state, which is different from the first state, in which the grindstones are held out of contact with the workpiece at a position where the grindstones overlap the rotational axis of the chuck table, and moving the holding surface and the grindstones relatively closer to each other to bring the grindstones into abrasive contact with the workpiece to thereby grind an outer circumferential portion of the workpiece, without grinding a central portion of the workpiece, wherein the second grinding step is performed after the grinding stopping step,
wherein, in the second grinding step, the workpiece is ground under a condition for causing the workpiece to have a smaller surface roughness than that in the first grinding step.