STRENGTHENED GLASS ARTICLES HAVING ETCHED FEATURES AND METHODS OF FORMING THE SAME

• US 20130273324A1
• Filed: 03/13/2013
• Published: 10/17/2013
• Est. Priority Date: 04/13/2012
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Moll, Johannes, Price, James Joseph, Ruffin, Alranzo Boh, Tsuda, Sergio, Wagner, Robert Stephen, Watkins, James Joseph
• Granted Patent: US 9,938,186 B2
• Time in Patent Office: Days
• US Class Current: 428/161
• CPC Class Codes: B41M 5/24 Ablative recording, e.g. by burning marks; Spark recording marking by high energetic means, e.g. by laser otherwise than burning or ablative removal B41M5/26; materials or methods for recording or reproduction by optical means G11B7/00
• CPC Class Codes: B44C 1/227 by etching
• CPC Class Codes: B44C 1/228 by laser radiation
• CPC Class Codes: C03C 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: C03C 23/0025 by a laser beam
• CPC Class Codes: Y10T 428/24479 including variation in thickness
• CPC Class Codes: Y10T 428/24521 with component conforming to contour of nonplanar surface

Abstract

Strengthened glass articles having laser etched features, electronic devices, and methods of fabricating etched features in strengthened glass articles are disclosed. In one embodiment, a strengthened glass article includes a first strengthened surface layer and a second strengthened surface layer under a compressive stress and extending from a first surface and a second surface, respectively, of the strengthened glass article to a depth of layer, and a central region between the first strengthened surface layer and the second strengthened surface layer that is under tensile stress. The strengthened glass article further includes at least one etched feature formed by laser ablation within the first surface or the second surface having a depth that is less than the depth of layer and a surface roughness that is greater than a surface roughness of the first surface or second surface outside of the at least one etched feature.

Claims

1. A method of fabricating a strengthened glass article having an etched feature, the method comprising:

providing a non-strengthened glass article comprising a first surface and a second surface;

focusing a laser beam onto the first surface of the non-strengthened glass article to ablate material from the first surface;

translating the laser beam relative to the non-strengthened glass article within a boundary defined by a desired etched feature, wherein translation of the laser beam ablates the material from the first surface at a depth to form the etched feature; and

chemically strengthening the non-strengthened glass article by a chemical strengthening process after forming the etched feature, wherein;

the strengthened glass article comprises a first strengthened surface layer and a second strengthened surface layer under a compressive stress and extending from the first surface and the second surface of the strengthened glass article, respectively, to a depth of layer, and a central region between the first strengthened surface layer and the second strengthened surface layer that is under tensile stress; and

the depth of the etched feature is less than the depth of layer such that the etched feature is within the compressive stress layer.

2. The method of claim 1, further comprising, prior to chemically strengthening the non-strengthened glass article, chemically etching the etched feature to reduce a surface roughness of a surface of the etched feature.

3. The method of claim 1, wherein the laser beam is a pulsed laser beam having a pulse width greater than 10 femtoseconds.

4. The method of claim 3, wherein the pulsed laser beam is pulsed at a frequency less than about 100 MHz.

5. The method of claim 3, wherein the pulsed laser beam is translated on the first surface of the non-strengthened glass article at a scan speed within a range of about 10 cm/s to about 120 cm/s.

6. The method of claim 1, wherein translating the laser beam comprises translating the laser beam within the boundary of the desired etched feature to form a plurality of first defect lines along a first direction.

7. The method of claim 6, wherein translating the laser beam further comprises translating the laser beam within the boundary of the desired etched feature to form a plurality of second defect lines along a second direction, wherein the plurality of first defect lines intersect the plurality of second defect lines.

8. The method of claim 1, wherein translating the laser beam creates a plurality of defect lines separated by a separation distance such that the plurality of defect lines create a diffractive grating within the boundary of the etched feature.

9. The method of claim 1, wherein translating the laser beam comprises translating the laser beam to form a two-dimensional pattern or three-dimensional pattern within the boundary of the desired etched feature.

10. The method of claim 1, further comprising applying one or more thin layers of material on the surface of the strengthened glass article such that the one or more thin layers of material are disposed on the etched feature.

18. The strengthened glass article of claim 1, further comprising one or more thin layers of material disposed on the surface of the strengthened glass article and the etched feature.

11. A strengthened glass article comprising:

a first strengthened surface layer and a second strengthened surface layer under a compressive stress and extending from a first surface and a second surface, respectively, of the strengthened glass article to a depth of layer, and a central region between the first strengthened surface layer and the second strengthened surface layer that is under tensile stress; and

at least one etched feature within the first surface or the second surface, the at least one etched feature comprising a depth that is less than the depth of layer and a surface roughness that is greater than a surface roughness of the first surface or the second surface outside of the at least one etched feature, wherein the at least one etched feature is formed by laser ablation.

12. The strengthened glass article of claim 11, wherein the depth of the at least one etched feature is within a range of about 10 μ

m to about 40 μ

m.

13. The strengthened glass article of claim 11, wherein the depth of layer of the strengthened glass article is greater than 5 μ

m and has a surface compression of greater than about 100 MPa.

14. The strengthened glass article of claim 11, wherein the at least one etched feature is defined by a plurality of intersecting defect lines that form a cross-hatch defect pattern.

15. The strengthened glass article of claim 11, wherein the at least one etched feature is defined by a two-dimensional pattern or a three-dimensional pattern within a boundary of the at least one etched feature.

16. The strengthened glass article of claim 11, wherein the at least one etched feature comprises a wall that separates the at least one etched feature from a surrounding surface of the strengthened glass article.

17. The strengthened glass article of claim 11, wherein:

the at least one etched feature comprises a plurality of defect lines separated by a separation distance; and

the separation distance is such that the plurality of defect lines create a diffractive grating within the boundary of the at least one etched feature.

19. A method of fabricating a strengthened glass article having an etched feature, the method comprising:

providing a strengthened glass substrate comprising a first surface and a second surface, wherein the strengthened glass article comprises a first strengthened surface layer and a second strengthened surface layer under a compressive stress and extending from the first surface and the second surface of the strengthened glass article, respectively, to a depth of layer, and a central region between the first strengthened surface layer and the second strengthened surface layer that is under tensile stress;

depositing one or more thin layers of material on the first surface and/or the second surface of the strengthened glass substrate;

focusing a laser beam onto the one or more thin layers of material; and

translating the laser beam relative to the strengthened glass substrate within a boundary defined by a desired etched feature, wherein translation of the laser beam ablates material from a first surface of the one or more thin layers of material at a depth to form the etched feature within the one or more thin layers of material, and the strengthened glass substrate remains undamaged from the laser beam.

20. The method of claim 19, wherein:

the etched feature comprises a plurality of defect lines separated by a separation distance; and

the separation distance is such that the plurality of defect lines create a diffractive grating within the boundary of the etched feature.