Laser processing apparatus

Patent metadata

Field	Value
Publication number	US-10071442-B2
Application number	US-201615091143-A
Country	US
Kind code	B2
Filing date	Apr 5, 2016
Priority date	Apr 9, 2015
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

A focusing unit of a laser processing apparatus includes: a focusing lens that focuses a laser beam oscillated from a laser beam oscillating unit; and a spherical aberration extending lens that extends the spherical aberration of the focusing lens. A pulsed laser beam is applied from the focusing unit to a workpiece held on a chuck table, to form shield tunnels each composed of a fine hole and an amorphous region shielding the fine hole, the shield tunnels extending from an upper surface toward a lower surface of the workpiece.

First claim

What is claimed is:

1. A laser processing apparatus comprising:
a chuck table that holds a workpiece;
laser beam applying means that applies a pulsed laser beam to the workpiece held on the chuck table; and
processing feeding means that moves the chuck table and the laser beam applying means relative to each other in a processing feed direction,
wherein the laser beam applying means includes laser beam oscillating means that oscillates a laser beam of such a wavelength as to be transmitted through the workpiece, and a focusing unit that focuses the laser beam oscillated from the laser beam oscillating means to apply the laser beam to the workpiece held on the chuck table,
the focusing unit includes a focusing lens that focuses the laser beam oscillated from the laser beam oscillating means, and a spherical aberration extending lens that selectively extends spherical aberration of the focusing lens, and
the pulsed laser beam is applied from the focusing unit to the workpiece held on the chuck table to form shield tunnels each composed of a fine hole and an amorphous region shielding the fine hole, the shield tunnels extending from an upper surface toward a lower surface of the workpiece,
wherein the spherical aberration extending lens extends the spherical aberration of the focusing lens in a range of from 100 to 500 μm.

2. The laser processing apparatus according to claim 1 , wherein the pulsed laser beam has a peak energy density set to within a range of from 1 to 100 TW/cm 2 .

Assignees

• Disco Corp

Inventors

• Morikazu Hiroshi
• Takeda Noboru
• Hirata Kazuya

Classifications

• H10P72/7416

  used during dicing or grinding · CPC title

• H10P72/7402

  Wafer tapes, e.g. grinding or dicing support tapes · CPC title

• H10P72/0428

  Apparatus for mechanical treatment or grinding or cutting · CPC title

• H10P72/0436

  mainly by radiation · CPC title

• H10P72/76

  using mechanical means, e.g. clamps or pinches · CPC title