Method for rapid laser drilling of holes in glass and products made therefrom

Patent metadata

Field	Value
Publication number	US-10293436-B2
Application number	US-201414535800-A
Country	US
Kind code	B2
Filing date	Nov 7, 2014
Priority date	Dec 17, 2013
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

Forming holes in a material includes focusing a pulsed laser beam into a laser beam focal line oriented along the beam propagation direction and directed into the material, the laser beam focal line generating an induced absorption within the material, the induced absorption producing a defect line along the laser beam focal line within the material, and translating the material and the laser beam relative to each other, thereby forming a plurality of defect lines in the material, and etching the material in an acid solution to produce holes greater than 1 micron in diameter by enlarging the defect lines in the material. A glass article includes a stack of glass substrates with formed holes of 1-100 micron diameter extending through the stack.

First claim

What is claimed is:

1. A method of forming holes in a substantially transparent material comprising:
focusing a pulsed laser beam into a laser beam focal line oriented along the beam propagation direction and directed into the material, the laser beam focal line generating an induced absorption within the material, the induced absorption producing a damage track along the laser beam focal line within the material, wherein the laser beam focal line does not rely upon Kerr-effect based self-focusing to produce the damage track within the material, the pulsed laser beam is focused by a focusing lens, and the pulsed laser beam irradiates the focusing lens in the form of an annulus;
translating the material and the laser beam relative to each other, thereby forming a plurality of damage tracks; and
etching the material in an acid solution to produce through-holes of a diameter greater than 1 micron by enlarging the damage tracks in the material.

2. The method of claim 1 , wherein the pulsed laser produces bursts with at least 2 pulses per burst and produces an energy of at least 40 μJ per burst.

3. The method of claim 1 , wherein the pulsed laser produces at least 500 damage tracks/sec.

4. The method of claim 1 , wherein the pulsed laser produces at least 1,000 damage tracks/sec.

5. The method of claim 1 , wherein the pulsed laser produces at least 5,000 damage tracks/sec.

6. The method of claim 1 , where the focal line is created by using a Bessel beam or a Gauss-Bessel beam.

7. The method of claim 1 , where the focal line is generated by using an axicon.

8. The method of claim 1 , wherein the material is transparent to at least one wavelength in a range from 390 nm to 700 nm.

9. The method of claim 1 , wherein the material can transmit at least 70% of at least one wavelength in a range from 390 nm to 700 nm.

10. The method of claim 1 , wherein the material is a glass.

11. The method of claim 1 , wherein the material is fused silica.

12. The method of claim 1 , wherein the material is a stack of glass sheets.

13. The method of claim 1 , wherein the etching is at a rate of less than about 10 microns/min.

14. The method of claim 1 , wherein the etching is at a rate of less than about 5 microns/min.

15. The method of claim 1 , wherein the etching is at a rate of less than about 2 microns/min.

16. The method of claim 1 , wherein a pulse duration of the pulsed laser beam is in a range of between greater than about 1 picosecond and less than about 100 picoseconds.

17. The method of claim 16 , wherein the pulse duration is in a range of between greater than about 5 picoseconds and less than about 20 picoseconds.

18. The method of claim 1 , wherein a repetition rate of the laser beam is in a range of between about 1 kHz and 4 MHz.

19. The method of claim 18 , wherein the repetition rate is in a range of between about 10 kHz and about 650 kHz.

20. The method of claim 1 , wherein the pulsed laser beam has a burst energy density, in a range from 25 microJoules/mm of line focus to 125 microJoules/mm of line focus.

21. The method of claim 1 , wherein pulses of the pulsed laser beam are produced in bursts of at least two pulses separated by a duration in a range of between about 1 nsec and about 50 nsec, and wherein a burst repetition frequency of the bursts is in a range of between about 1 kHz and about 650 kHz.

22. The method of claim 21 , wherein the at least pulses are separated by a duration of 20 nsec plus or minus 2 nsec.

23. The method of claim 1 , wherein the pulsed laser beam has a wavelength selected such that the material is substantially transparent at the wavelength.

24. The method of claim 1 , wherein the laser beam focal line has a length in a range of between about 0.1 mm and about 10 mm.

25. The method of claim 24 , wherein the laser beam focal line has a length in a range of between about 0.1 mm and about 1 mm.

26. The method of claim 1 , wherein the laser beam focal line has an average spot diameter in a range of between about 0.1 micron and about 5 microns.

27. The method of claim 1 , wherein the damage tracks each have a diameter less than or equal to about 5 microns.

28. The method of claim 1 , wherein a spacing between adjacent damage tracks is between 50 microns and 500 microns.

29. The method of claim 28 , wherein the spacing between adjacent damage tracks is between 10 microns and 50 microns.

30. The method of claim 1 , wherein translating the material and the laser beam relative to each other comprises translating the laser beam using a resonant scanning mirror scanner.

31. The method of claim 1 , wherein translating the material and the laser beam relative to each other comprises translating the laser beam using a galvanometer mirror scanner.

32. The method of claim 1 , wherein translating the material and the laser beam relative to each other comprises translating the laser beam using an acousto-optic deflector.

33. The method of claim 1 , wherein the damage tracks are made in an aperiodic pattern.

34. The method of claim 1 , further comprising coating interior surfaces of the through-holes with an electrical conductor to produce electrical conductivity between a top and a bottom of the through-holes.

35. The method of claim 1 , further comprising coating interior surfaces of the through-holes to facilitate attachment of biomolecules.

36. A method of forming holes in a substantially transparent material comprising:
focusing a pulsed laser beam into a laser beam focal line oriented along the beam propagation direction and directed into the material, the laser beam focal line generating an induced absorption within the material, the induced absorption producing a damage track along the laser beam focal line within the material, wherein:
the laser beam focal line is formed by a series of focal points and comprises a length that extends from a first end focal point to a second end focal point;
the first end focal point and the second end focal point each comprise an intensity that is one half the maximum intensity of the laser beam focal line;
the pulsed laser beam is focused by a focusing lens; and
the pulsed laser beam irradiates the focusing lens in the form of an annulus;

translating the material and the laser beam relative to each other, thereby forming a plurality of damage tracks; and
etching the material in an acid solution to produce through-holes of a diameter greater than 1 micron by enlarging the damage tracks in the material.

37. The method of claim 36 , wherein the etching is at a rate of less than about 10 microns/min.

38. The method of claim 36 , wherein pulses of the pulsed laser beam are produced in bursts of at least two pulses separated by a duration in a range of between about 1 nsec and about 50 nsec, and wherein a burst repetition frequency of the bursts is in a range of between about 1 kHz and about 650 kHz.

39. The method of claim 36 , wherein the length of the laser beam focal line is in a range of between about 0.1 mm and about 10 mm.

40. The method of claim 36 , wherein the laser beam focal line has an average spot diameter in a range of between about 0.1 micron and about 5

Assignees

• Corning Inc

Inventors

• Marjanovic Sasha
• Piech Garrett Andrew
• Shanmugam Shyamala
• Tsuda Sergio
• Wagner Robert Stephen

Classifications

• Y10T428/24322

  Composite web or sheet · CPC title

• B23K26/04

  Automatically aligning, aiming or focusing the laser beam, e.g. using the back-scattered light · CPC title

• B23K26/0617

  and with spots spaced along the common axis · CPC title

• B23K26/38

  by boring or cutting · CPC title

• C03B33/0222

  Scoring using a focussed radiation beam, e.g. laser · CPC title