Ceramic-based components having laser-etched markings

• US 10,639,746 B1
• Filed: 02/24/2015
• Issued: 05/05/2020
• Est. Priority Date: 06/20/2014
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Nashner, Michael S., Russell-Clarke, Peter N.
• Primary Examiner(s): Gaitonde, Megha M
• Application Number:
  US14/630,230
• Time in Patent Office: 1,897 Days
• Field of Search: 428156, 428161, 428164, 428172, 428173
• CPC Class Codes: B23K 2103/52 Ceramics
• CPC Class Codes: B23K 26/354 by melting
• CPC Class Codes: B23K 26/362 Laser etching
• CPC Class Codes: B23K 26/364 for making a groove or trench, e.g. for scribing a break initiation groove
• CPC Class Codes: B23K 26/40 taking account of the properties of the material involved
• CPC Class Codes: H05K 5/0252 Labels, e.g. for identification, markings or configuration store

Abstract

A ceramic-based component including laser-etched markings, an electronic device including a ceramic-based component, and methods of forming the same. The ceramic-based component may include an outer surface, and a laser-etched marking formed on the outer surface. The laser-etched marking may include a recess having a substantially uneven surface formed in the outer surface. The recess may have a material composition distinct from a material composition of the outer surface. The method of forming the ceramic-based component may include laser etching an outer surface of a ceramic-based component, and in response to the laser etching, forming a laser-etched marking on the outer surface of the ceramic-based component. The method may also include altering the optically reflective properties of the laser-etched marking and/or altering a material composition of the laser-etched marking relative to a distinct material composition of the outer surface of the ceramic-based component.

Claims

1. A ceramic-based housing for an electronic device, comprising:

a component formed from a ceramic material and defining an outer surface, the ceramic material comprising a first ratio of zirconium to aluminum;

a laser-etched blind recess formed into the component by ablating the ceramic material and defining at least a portion of a glyph; and

a marking defined by a bottom surface of the laser-etched blind recess and a raised portion extending above the outer surface and surrounding the laser-etched blind recess, the marking having an altered material composition of the ceramic material resulting from a melting and resolidification of the ceramic material, the marking having a second ratio of zirconium to aluminum, the second ratio different from the first ratio, and being optically distinct from a portion of the outer surface adjacent the marking, wherein

the portion of the outer surface of the ceramic material adjacent the marking is defined by an unaltered material composition of the ceramic material.

2. The ceramic-based housing of claim 1, wherein the outer surface comprises a first color that is one of black or white.

3. The ceramic-based housing of claim 2, wherein the laser-etched blind recess comprises a second color that is one of black or white, distinct from the first color.

4. The ceramic-based housing of claim 1, further comprising a heat affected region positioned adjacent to the laser-etched blind recess, the heat affected region positioned below the outer surface.

13. The ceramic-based housing of claim 1, wherein the laser-etched blind recess extends into the outer surface by less than 8 microns.

14. The ceramic-based housing of claim 1, wherein:

the ceramic material is zirconia alumina.

16. The ceramic-based housing of claim 4, wherein the heat affected region is positioned below the outer surface by a distance between approximately 5 microns and approximately 14 microns.

5. A ceramic-based housing for an electronic device, comprising:

a ceramic component defining;

an exterior surface comprising a first ceramic material having a first group of constituent material elements including zirconium and aluminum in a first ratio to one another;

a blind recess within the ceramic component; and

a marking defined by a surface of the blind recess and a raised feature surrounding the blind recess, the marking;

comprising a second ceramic material having a second group of constituent material elements including zirconium and aluminum in a second ratio to one another, the second ratio different from the first ratio;

formed from a resolidified portion of the second ceramic material that is melted when the ceramic component is ablated;

exhibiting an optical contrast with respect to the exterior surface; and

defining at least a portion of a glyph.

6. The ceramic-based housing of claim 5, wherein the surface of the blind recess is an uneven surface that non-uniformly reflects incident light.

7. The ceramic-based housing of claim 5, wherein the surface of the blind recess has a different color than the exterior surface.

8. The ceramic-based housing of claim 5, wherein the exterior surface is at least partially formed via an annealing process that reflows a portion of the exterior surface to form a planar, polished first surface.

9. The ceramic-based housing of claim 5, further comprising a reflective coating on at least one of the exterior surface or the surface of the blind recess.

17. The ceramic-based housing of claim 5, wherein the ablating is performed with a laser having an ultraviolet wavelength.

20. The ceramic-based housing of claim 5, wherein:

a depth of the blind recess below the exterior surface of the ceramic component is between 2 microns and 8 microns; and

a height of the raised feature above the exterior surface of the ceramic component is between 1.4 microns and 2.5 microns.

10. An electronic device, comprising:

a housing component having a first ceramic composition having a first ratio of zirconium to aluminum, the housing component defining;

a surface; and

a marking defined by;

a laser-ablated groove formed into the housing component along the surface; and

a raised rim surrounding the laser-ablated groove, the raised rim and a surface of the laser-ablated groove formed of a second ceramic composition formed as a result of the laser ablation, the second ceramic composition having a second ratio of zirconium to aluminum, the second ratio different than the first ratio,

wherein the marking defines an exterior surface of the housing component that is optically contrasting with respect to a remainder of the surface having the first ceramic composition; and

a display at least partially positioned within the housing component.

11. The electronic device of claim 10, wherein the optical contrast is due, at least in part, to the second ceramic composition having a different ratio of zirconium to aluminum.

12. The electronic device of claim 10, wherein the optical contrast is due, at least in part, to a non-uniformity of the marking.

15. The electronic device of claim 10, wherein:

the first ceramic composition corresponds to a zirconia alumina ceramic; and

the second ceramic composition corresponds to a zirconia ceramic.

18. The electronic device of claim 10, wherein the laser-ablated groove is formed by a laser having operational parameters comprising:

a laser wavelength of 355 nm; and

a pulse width of 20 ns.

19. The electronic device of claim 10, wherein a height of the raised rim surrounding the laser-ablated groove above the surface is between approximately 1.4 microns and approximately 2.5 microns.