US 12,064,847 B2
Processing method of 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. 17/656,354.
Claims priority of application No. 2021-065241 (JP), filed on Apr. 7, 2021.
Prior Publication US 2022/0324082 A1, Oct. 13, 2022
Int. Cl. B24B 7/04 (2006.01); B24B 7/22 (2006.01); B24B 37/27 (2012.01); B24B 37/34 (2012.01)
CPC B24B 37/345 (2013.01) [B24B 7/04 (2013.01); B24B 7/228 (2013.01); B24B 37/27 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A processing method of grinding a workpiece, comprising:
a holding step of holding the workpiece on a side of a front surface thereof on a holding surface of a chuck table having an axis of rotation set along a direction perpendicular to the holding surface;
a coarse grinding step of, after performing the holding step, adjusting a positional relationship between the chuck table and a first grinding wheel such that a moving path of first grinding stones, which are included on the first grinding wheel and contain first abrasive grains, overlaps the axis of rotation of the chuck table, and grinding the workpiece on an entire side of a back surface thereof with the first grinding stones until the workpiece has a predetermined thickness;
an auxiliary grinding step of, after performing the coarse grinding step, adjusting the positional relationship between the chuck table and the first grinding wheel such that the first grinding stones overlap an inner side of an outer peripheral edge of the workpiece, and grinding the workpiece on the side of the back surface thereof with the first grinding stones such that an unground region remains at an outer peripheral portion of the workpiece;
an unground region grinding step of, after performing the auxiliary grinding step, adjusting a positional relationship between the chuck table and a second grinding wheel such that a moving path of second grinding stones, which are included on the second grinding wheel and contain second abrasive grains having a smaller average grain size than that of the first abrasive grains, overlaps the axis of rotation of the chuck table, and grinding the unground region with the second grinding stones; and
a finish grinding step of, after performing the unground region grinding step, grinding the workpiece on the side of the back surface thereof with the second grinding stones until the workpiece has a predetermined finish thickness.