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US-20260124699-A1 - LASER PROCESSING APPARATUS AND ELECTRONIC DEVICE MANUFACTURING METHOD

US20260124699A1US 20260124699 A1US20260124699 A1US 20260124699A1US-20260124699-A1

Abstract

A laser processing apparatus according to one aspect of the present disclosure performs hole processing on a workpiece using a pulse laser beam output from a laser apparatus, and includes a Z polarizer disposed on an optical path of the pulse laser beam and configured to convert a polarization state of the pulse laser beam to azimuthal polarization, a diffractive optical element configured to split the azimuthally polarized pulse laser beam transmitted through the Z polarizer into a plurality of laser beams, and a light condensing optical system configured to generate a plurality of light condensing spots on the workpiece by condensing the laser beams.

Inventors

  • Tomonari Tanaka

Assignees

  • GIGAPHOTON INC.

Dates

Publication Date
20260507
Application Date
20251002
Priority Date
20241107

Claims (20)

  1. 1 . A laser processing apparatus that performs hole processing on a workpiece using a pulse laser beam output from a laser apparatus, the laser processing apparatus comprising: a Z polarizer disposed on an optical path of the pulse laser beam and configured to convert a polarization state of the pulse laser beam to azimuthal polarization; a diffractive optical element configured to split the azimuthally polarized pulse laser beam transmitted through the Z polarizer into a plurality of laser beams; and a light condensing optical system configured to generate a plurality of light condensing spots on the workpiece by condensing the laser beams.
  2. 2 . The laser processing apparatus according to claim 1 , wherein the Z polarizer is disposed so that a center coincides with an optical axis of the pulse laser beam.
  3. 3 . The laser processing apparatus according to claim 1 , wherein the diffractive optical element is disposed so that a center coincides with an optical axis of the pulse laser beam.
  4. 4 . The laser processing apparatus according to claim 1 , wherein the Z polarizer is formed by combining a plurality of ½ wave plates of different optical axis directions.
  5. 5 . The laser processing apparatus according to claim 4 , wherein the number of the ½ wave plates is between 4 and 12.
  6. 6 . The laser processing apparatus according to claim 1 , wherein the pulse laser beam output from the laser apparatus is linearly polarized, and the linearly polarized pulse laser beam is incident on the Z polarizer.
  7. 7 . The laser processing apparatus according to claim 1 , comprising a rotating stage that holds the Z polarizer rotatably with an optical axis of the pulse laser beam as a rotation axis.
  8. 8 . The laser processing apparatus according to claim 7 , wherein the Z polarizer is disposed so that a center coincides with the rotation axis.
  9. 9 . The laser processing apparatus according to claim 1 , comprising a first moving stage that holds the Z polarizer movably in a direction orthogonal to an optical axis of the pulse laser beam.
  10. 10 . The laser processing apparatus according to claim 1 , comprising a second moving stage that holds the diffractive optical element movably in a direction orthogonal to an optical axis of the pulse laser beam.
  11. 11 . The laser processing apparatus according to claim 1 , wherein the Z polarizer is a polarization converter that sets a polarization direction of the azimuthal polarization to a direction along a circumference.
  12. 12 . The laser processing apparatus according to claim 1 , wherein the Z polarizer and the diffractive optical element are integrated as a multi-spot polarization converter.
  13. 13 . The laser processing apparatus according to claim 12 , wherein the multi-spot polarization converter includes a substrate, and the Z polarizer and the diffractive optical element are formed in the substrate.
  14. 14 . The laser processing apparatus according to claim 13 , wherein the Z polarizer is formed along an incident surface of the substrate, and the diffractive optical element is formed along an exit surface of the substrate.
  15. 15 . The laser processing apparatus according to claim 13 , wherein the Z polarizer is formed inside the substrate, and the diffractive optical element is formed along an exit surface of the substrate.
  16. 16 . The laser processing apparatus according to claim 13 , wherein the Z polarizer is formed along an exist surface of the substrate, and the diffractive optical element is formed along the exit surface of the substrate.
  17. 17 . The laser processing apparatus according to claim 13 , wherein the Z polarizer is formed along an incident surface of the substrate, and the diffractive optical element is formed along the incident surface of the substrate.
  18. 18 . The laser processing apparatus according to claim 12 , comprising a rotating stage that holds the multi-spot polarization converter rotatably with an optical axis of the pulse laser beam as a rotation axis.
  19. 19 . The laser processing apparatus according to claim 12 , comprising a moving stage that holds the multi-spot polarization converter movably in a direction orthogonal to an optical axis of the pulse laser beam.
  20. 20 . An electronic device manufacturing method comprising: producing an interposer by laser processing an interposer substrate with a laser processing apparatus, the laser processing apparatus configured to perform hole processing on a workpiece using a pulse laser beam output from a laser apparatus, the laser processing apparatus including a Z polarizer disposed on an optical path of the pulse laser beam and configured to convert a polarization state of the pulse laser beam to azimuthal polarization, a diffractive optical element configured to split the azimuthally polarized pulse laser beam transmitted through the Z polarizer into a plurality of laser beams, and a light condensing optical system configured to generate a plurality of light condensing spots on the workpiece by condensing the laser beams; coupling and electrically connecting the interposer and an integrated circuit chip to each other; and coupling and electrically connecting the interposer and a circuit board to each other.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS The present application claims the benefit of Japanese Patent Application No. 2024-195486, filed on Nov. 7, 2024, the entire contents of which are hereby incorporated by reference. BACKGROUND 1. Technical Field The present disclosure relates to a laser processing apparatus and an electronic device manufacturing method. 2. Related Art Recently, an improvement in resolutions of semiconductor exposure devices has been desired with miniaturization and high integration of semiconductor integrated circuits. For this purpose, an exposure light source that outputs light having a shorter wavelength has been developed. For example, as a gas laser apparatus for exposure, a KrF excimer laser apparatus that outputs a laser beam having a wavelength of about 248.4 nm and an ArF excimer laser apparatus that outputs a laser beam having a wavelength of about 193.4 nm are used. In addition, an excimer laser beam has a pulse width of about several tens of ns and, due to its short wavelength, is sometimes used for direct processing of polymer materials and glass materials or the like. A chemical bond in a polymer material can be cut by an excimer laser beam having photon energy higher than bond energy. Therefore, it is known that non-heating processing of a polymer material is made possible by an excimer laser beam, and a processing shape becomes smooth. In addition, since glass, ceramics, and the like have a high absorptance to an excimer laser beam, it is known that even a material that is difficult to be processed by a visible and infrared laser beam can be processed by an excimer laser beam. LIST OF DOCUMENTS Patent Documents Patent Document 1: U.S. Pat. No. 7,880,117Patent Document 2: Japanese Unexamined Patent Application Publication No. 2022-060850Patent Document 3: International Publication No. WO 2023/099946 SUMMARY A laser processing apparatus according to one aspect of the present disclosure performs hole processing on a workpiece using a pulse laser beam output from a laser apparatus, and includes a Z polarizer, a diffractive optical element, and a light condensing optical system. The Z polarizer is disposed on an optical path of the pulse laser beam and is configured to convert a polarization state of the pulse laser beam to azimuthal polarization. The diffractive optical element is configured to split the azimuthally polarized pulse laser beam transmitted through the Z polarizer into a plurality of laser beams. The light condensing optical system is configured to generate a plurality of light condensing spots on the workpiece by condensing the laser beams. An electronic device manufacturing method according to one aspect of the present disclosure includes producing an interposer by laser processing an interposer substrate with a laser processing apparatus, coupling and electrically connecting the interposer and an integrated circuit chip to each other, and coupling and electrically connecting the interposer and a circuit board to each other. The laser processing apparatus performs hole processing on a workpiece using a pulse laser beam output from a laser apparatus, and includes a Z polarizer disposed on an optical path of the pulse laser beam and configured to convert a polarization state of the pulse laser beam to azimuthal polarization, a diffractive optical element configured to split the azimuthally polarized pulse laser beam transmitted through the Z polarizer into a plurality of laser beams, and a light condensing optical system configured to generate a plurality of light condensing spots on the workpiece by condensing the laser beams. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present disclosure will be described below merely as examples with reference to the accompanying drawings. FIG. 1 is a diagram schematically illustrating a configuration of a laser processing system according to a comparative example. FIG. 2 is a diagram schematically illustrating a configuration of a laser apparatus. FIG. 3 is a diagram schematically illustrating a configuration of a laser processing system according to a first embodiment. FIG. 4 is a diagram illustrating a configuration example of a Z polarizer. FIG. 5 is a diagram illustrating an action of the Z polarizer. FIG. 6 is a diagram describing position adjustment of the Z polarizer. FIG. 7 is a diagram illustrating an example of a laser beam incident on an inner wall of a hole during hole processing. FIG. 8 is a diagram illustrating an example of a laser beam incident on an inner wall of a hole during hole processing. FIG. 9 is a diagram describing a polarization state on an inner wall when a linearly polarized laser beam is incident on a hole. FIG. 10 is a diagram describing a polarization state on an inner wall when an azimuthally polarized laser beam is incident on a hole. FIG. 11 is a diagram illustrating a configuration of a Z polarizer according to a modification. FIG. 12 is a diagram illustrating an action of the Z