US 12,170,211 B2
Laser processing apparatus
Yuta Yoshida, Tokyo (JP)
Assigned to DISCO CORPORATION, Tokyo (JP)
Filed by DISCO CORPORATION, Tokyo (JP)
Filed on Dec. 15, 2020, as Appl. No. 17/122,060.
Claims priority of application No. 2019-237460 (JP), filed on Dec. 26, 2019.
Prior Publication US 2021/0202278 A1, Jul. 1, 2021
Int. Cl. H01L 21/67 (2006.01); B23K 26/06 (2014.01); B23K 26/073 (2006.01); B23K 26/08 (2014.01); B23K 26/364 (2014.01); G02B 19/00 (2006.01); G02B 27/09 (2006.01); H01L 21/687 (2006.01)
CPC H01L 21/67092 (2013.01) [B23K 26/0648 (2013.01); B23K 26/073 (2013.01); B23K 26/0853 (2013.01); B23K 26/364 (2015.10); G02B 19/0009 (2013.01); G02B 19/0047 (2013.01); G02B 27/0927 (2013.01); G02B 27/0966 (2013.01); H01L 21/67115 (2013.01); H01L 21/68764 (2013.01); B23K 26/0665 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A laser processing apparatus comprising:
a chuck table that holds a workpiece;
a laser beam irradiation unit that irradiates the workpiece held by the chuck table with a laser beam with a wavelength having absorbability with respect to the workpiece;
an X-axis direction movement unit that moves the chuck table and the laser beam irradiation unit relatively in an X-axis direction that is a processing feed direction; and
a Y-axis direction movement unit that moves the chuck table and the laser beam irradiation unit relatively in a Y-axis direction that is an indexing feed direction orthogonal to the processing feed direction,
wherein the laser beam irradiation unit includes:
a laser oscillator,
a condensing lens that condenses the laser beam emitted from the laser oscillator,
an energy distribution correcting unit that is disposed between the laser oscillator and the condensing lens and forms skirt parts of a Gaussian distribution of an energy distribution in the Y-axis direction regarding the laser beam emitted from the laser oscillator into a perpendicular distribution,
an imaging lens group composed of two or more lenses that form an image of a beam shape of the laser beam for which the energy distribution has been corrected by the energy distribution correcting unit on an upper surface of the workpiece, wherein relative positions of the two or more lenses of the imaging lens group are fixed with respect to each other, wherein the imaging lens group includes a spherical biconcave lens, and
one cylindrical lens that adjusts energy density in the X-axis direction regarding the laser beam for which the energy distribution has been corrected by the energy distribution correcting unit,
wherein a distance between the imaging lens group and the one cylindrical lens is relatively moved to adjust a spot shape of the laser beam on the upper surface of the workpiece.