US 12,472,585 B2
Adjustment method of laser processing apparatus, and laser processing apparatus
Yuki Ikku, Tokyo (JP); and Jun Abatake, Tokyo (JP)
Assigned to DISCO CORPORATION, Tokyo (JP)
Filed by DISCO CORPORATION, Tokyo (JP)
Filed on Apr. 21, 2022, as Appl. No. 17/660,119.
Claims priority of application No. 2021-073242 (JP), filed on Apr. 23, 2021.
Prior Publication US 2022/0339737 A1, Oct. 27, 2022
Int. Cl. B23K 26/359 (2014.01); B23K 26/03 (2006.01); B23K 26/067 (2006.01); B23K 103/00 (2006.01)
CPC B23K 26/359 (2015.10) [B23K 26/032 (2013.01); B23K 26/0676 (2013.01); B23K 2103/56 (2018.08)] 2 Claims
OG exemplary drawing
 
1. A laser processing apparatus comprising:
a chuck table that holds a workpiece;
a laser application unit that applies a laser beam to the workpiece held on the chuck table;
a feed mechanism that relatively feeds the chuck table and the laser application unit for processing; and
a control unit,
the laser application unit including
a laser oscillator that emits the laser beam,
a condenser that condenses and applies the laser beam that has been emitted from the laser oscillator to the workpiece held on the chuck table,
a spatial light modulator arranged between the laser oscillator and the condenser,
a spectrometer arranged between the condenser and the spatial light modulator, and
a camera arranged on a side toward which light reflected at the workpiece is split by the spectrometer,
the control unit including
a spatial light modulator adjustment instructions section configured to adjust the spatial light modulator into a state ready for splitting the laser beam that has been emitted from the laser oscillator, and applying a plurality of laser beams such that the laser beams will have a desired positional relation,
a processing mark formation instructions section configured to operate the laser oscillator to apply the laser beams to a wafer held as the workpiece on the chuck table such that a plurality of processing marks is formed at the wafer,
an imaging instructions section configured to stop the operation of the laser oscillator, and to image by the camera the processing marks formed at the wafer held on the chuck table, and
an aberration correction instructions section configured to correct aberration of the condenser by comparing the desired positional relation that has been instructed by the spatial light modulator adjustment instructions sections and a positional relation among the processing marks imaged by the camera, and adjusting the spatial light modulator such that the positional relation among the processing marks conforms to the desired positional relation.