US 11,673,229 B2
Processing apparatus
Toshiyuki Sakai, Tokyo (JP)
Assigned to DISCO CORPORATION, Tokyo (JP)
Filed by DISCO CORPORATION, Tokyo (JP)
Filed on Sep. 2, 2020, as Appl. No. 17/10,343.
Claims priority of application No. JP2019-163637 (JP), filed on Sep. 9, 2019.
Prior Publication US 2021/0069859 A1, Mar. 11, 2021
Int. Cl. B24B 49/12 (2006.01); B24B 7/22 (2006.01); B24B 37/24 (2012.01); B24B 37/10 (2012.01)
CPC B24B 49/12 (2013.01) [B24B 7/228 (2013.01); B24B 37/10 (2013.01); B24B 37/245 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A processing apparatus that polishes a back surface side of a wafer on which devices are formed on a front surface side, the processing apparatus comprising:
a chuck table that holds the wafer and rotates;
a polishing unit that forms scratches on the back surface side of the wafer while polishing the back surface side of the wafer by pressing a polishing pad containing abrasive grains against the back surface side of the wafer held by the chuck table while rotating the polishing pad;
a scratch determining unit that determines whether or not the scratches exist on the back surface side of the wafer polished by the polishing unit; and
an informing unit that informs an operator when a region for which it has been determined that the scratches do not exist by the scratch determining unit is included in the wafer, and
wherein:
the scratch determining unit includes a camera that images the wafer and obtains an image of the back surface side of the wafer,
the scratch determining unit determines whether or not the scratches exist based on a difference in contrasting density of the image obtained by the camera between a region in which the scratches exist and a region in which the scratches do not exist, and
the scratch determining unit includes an image processing section that converts the difference in contrasting density to a numerical value, and determines that the scratches exist when the numerical value exceeds a predetermined threshold.