SYSTEM AND METHOD FOR LASER BEVELING AND/OR POLISHING

• US 20190314934A1
• Filed: 05/24/2019
• Published: 10/17/2019
• Est. Priority Date: 08/28/2014
• Status: Active Grant

• Current Assignee: IPG Photonics Corporation
• Original Assignee: IPG Photonics Corporation
• Inventors: Sercel, Jeffrey P., Mendes, Marco, Sarrafi, Rouzbeh, Schoenly, Joshua, Song, Xiangyang, Hannon, Mathew, Sokol, Miroslaw
• Granted Patent: US 11,565,350 B2
• Time in Patent Office: Days
• CPC Class Codes: B23K 2103/50 Inorganic material, e.g. metals, not provided for in B23K2103/02 – B23K2103/26
• CPC Class Codes: B23K 2103/52 Ceramics
• CPC Class Codes: B23K 2103/54 Glass
• CPC Class Codes: B23K 2103/56 semiconducting semiconducting devices B23K2101/40
• CPC Class Codes: B23K 26/0624 using ultrashort pulses, i.e. pulses of 1ns or less
• CPC Class Codes: B23K 26/082 Scanning systems, i.e. devices involving movement of the laser beam relative to the laser head
• CPC Class Codes: B23K 26/0823 Devices involving rotation of the workpiece
• CPC Class Codes: B23K 26/0853 Devices involving movement of the workpiece in at least in two axial directions, e.g. in a plane
• CPC Class Codes: B23K 26/354 by melting
• CPC Class Codes: B23K 26/3576 Diminishing rugosity, e.g. grinding; Polishing; Smoothing
• CPC Class Codes: B23K 26/361 for deburring or mechanical trimming B23K26/351 takes precedence
• CPC Class Codes: B23K 26/38 by boring or cutting
• CPC Class Codes: B23K 26/402 involving non-metallic material, e.g. isolators

Abstract

Laser processing of hard dielectric materials may include cutting a part from a hard dielectric material using a continuous wave laser operating in a quasi-continuous wave (QCW) mode to emit consecutive laser light pulses in a wavelength range of about 1060 nm to 1070 nm. Cutting using a QCW laser may be performed with a lower duty cycle (e.g., between about 1% and 15%) and in an inert gas atmosphere such as nitrogen, argon or helium. Laser processing of hard dielectric materials may further include post-cut processing the cut edges of the part cut from the dielectric material, for example, by beveling and/or polishing the edges to reduce edge defects. The post-cut processing may be performed using a laser beam with different laser parameters than the beam used for cutting, for example, by using a shorter wavelength (e.g., 193 nm excimer laser) and/or a shorter pulse width (e.g., picosecond laser).

Claims

1. A method for post-cut processing cut edges of a part, the method comprising:

providing a cut part having cut edges with edge defects, wherein the cut part was cut from a hard dielectric material using a first laser beam;

generating a second laser beam with parameters capable of providing sufficient absorption in the hard dielectric material to modify the material such that the edge defects are reduced, wherein the second laser beam has a shorter wavelength and/or a shorter pulse width than the first laser beam; and

moving the cut part and the second laser beam relative to each other such that the second laser beam post-cut processes the edges of the part to reduce the edge defects.

2. The method of claim 1 wherein the first laser beam is generated by an IR single mode fiber laser operating in a quasi-continuous wave (QCW) mode, and wherein the second laser beam is generated by a green fiber laser.

3. The method of claim 1 wherein the first laser beam is generated by an IR single mode fiber laser operating in a quasi-continuous wave (QCW) mode, and wherein the second laser beam is generated by an ultrafast laser.

4. The method of claim 1 further comprising directing the second laser beam such that the second laser beam is angled with an angle of incidence that is greater than 0°

and less than the critical angle.

5. The method of claim 1 further comprising providing a first laser to generate the first laser beam.

6. The method of claim 5 wherein the first laser is an IR single mode fiber laser operating in a quasi-continuous wave (QCW) mode.

7. The method of claim 5 further comprising providing a second laser to generate the second laser beam.

8. The method of claim 7 wherein the second laser is an excimer laser.

9. The method of claim 7 wherein the second laser is an ultrafast laser.

10. The method of claim 9 wherein the second laser beam generated by the ultrafast laser has a wavelength in the IR range, the green range or the UV range.

11. The method of claim 7 wherein the second laser is a fiber laser configured to generate the second laser beam with a wavelength in the green range.

12. The method of claim 1 wherein the second laser beam post-cut processes the edges of the part by ablating material at the edges of the part.

13. The method of claim 1 wherein the second laser beam post-cut processes the edges of the part by melting material at the edges of the part.

14. The method of claim 1 wherein the second laser beam post-cut processes the edges of the part by beveling the edges of the part to form rounded bevels.

15. The method of claim 1 further comprising directing the second laser beam such that the second laser beam is angled with an angle of incidence that is greater than 0°

and less than the critical angle, wherein moving the cut part includes moving the cut part with coordinated motion in multiple axes relative to the angled laser beam.

16. The method of claim 15 wherein moving the cut part relative to the angled laser beam changes an orientation of the angled laser beam relative to an edge of the cut part to change a cut angle of the laser beam at the edge of the part while the laser angle remains the same.

17. The method of claim 16, wherein the cut angle of the laser beam is changed within a range of cut angles to form a rounded bevel on at least a portion of the edge of the part.

18. The method of claim 1 wherein the part is circular.