Methods for laser cutting glass substrates

Patent metadata

Field	Value
Publication number	US-9533910-B2
Application number	US-201414567083-A
Country	US
Kind code	B2
Filing date	Dec 11, 2014
Priority date	Aug 28, 2009
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A method for cutting a glass article from a strengthened glass substrate having a surface compression layer and a tensile layer includes forming an edge defect in the surface compression layer on a first edge of the strengthened glass substrate. The method further includes propagating a through vent through the surface compression and tensile layers at the edge defect. The through vent precedes a region of separation along a cut line between the glass article and the strengthened glass substrate.

First claim

What is claimed is:

1. A method of cutting a strengthened glass substrate comprising a surface compression layer and a tensile layer, the method comprising sequentially scanning a laser beam that is incident on the surface compression layer back and forth between a first edge of the strengthened glass substrate and a second edge of the strengthened glass substrate to create a tensile stress field that is present along an entire length of a cut line such that a through vent propagates along the cut line.

2. The method of claim 1 , wherein the surface compression layer has a depth greater than or equal to 40 μm.

3. The method of claim 1 , wherein the surface compression layer has a surface compression greater than 750 MPa.

4. The method of claim 1 , wherein:
the laser beam is scanned at a reference scanning speed when the laser beam is at a normal incidence angle relative to the strengthened glass substrate; and
the laser beam is scanned at a decreasing scanning speed that decreases from the reference scanning speed in accordance with an increasing angle of incidence of the laser beam as the laser beam is scanned along the cut line.

5. The method of claim 1 , further comprising forming an edge defect on the first edge of the strengthened glass substrate.

6. The method of claim 5 , further comprising scanning the laser beam back and forth along a shortened scan line on the edge defect after scanning the laser beam back and forth along the entire length of the cut line for a period of time.

7. The method of claim 5 , wherein the method further comprises applying a water jet to the edge defect after scanning the laser beam along the entire length of the cut line for a period of time.

8. The method of claim 1 , wherein the laser beam is generated by a pulsed CO 2 laser operated at a frequency within a range of 0 Hz to 200 kHz.

9. The method of claim 1 , further comprising shaping the laser beam such that the laser beam illuminates an elliptical beam spot on the strengthened glass substrate, the elliptical beam spot having a major axis that is aligned with the cut line.

10. The method of claim 1 , wherein sequentially scanning the laser beam back and forth creates a scanned laser line having a length that is equal to or greater than a length of the cut line.

Assignees

• Corning Inc

Inventors

• Li Xinghua
• Moore Lisa Anne

Classifications

• Y02P40/57

  Improving the yield, e-g- reduction of reject rates · CPC title

• C03B33/091 Primary

  using at least one focussed radiation beam, e.g. laser beam (C03B33/0955 takes precedence) · CPC title

• B23K26/40

  taking account of the properties of the material involved · CPC title

• B23K26/00

  Working by laser beam, e.g. welding, cutting or boring · CPC title

• B23K2203/50

  Operations & Transport · mapped topic