Full perimeter chemical strengthening of substrates

• US 9,405,388 B2
• Filed: 09/17/2010
• Issued: 08/02/2016
• Est. Priority Date: 06/30/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Feinstein, Casey J., Zhong, John Z.
• Primary Examiner(s): SNELTING, ERIN LYNN
• Application Number:
  US12/885,376
• Publication Number:
  US 20110005820A1
• Time in Patent Office: 2,146 Days
• Field of Search: 65/301, 65/301.4, 65/31, 651/04, 651/05, 216/20, 216/83, 216/97
• US Class Current: 1/1
• CPC Class Codes: C03C 15/00 Surface treatment of glass, not in the form of fibres or filaments, by etching etching or surface-brightening compositions, in general C09K13/00
• CPC Class Codes: C03C 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]

Abstract

Methods and apparatus for protecting the thin films during chemical and/or thermal edge strengthening treatment. In one embodiment, a portion of each individual sheet is laminated. Pairs of sheets are then sealed together such that the thin film sides face inward to form a thin film sandwich. In some embodiments, the sandwich in then immersed in a chemical strengthener. In other embodiments, a localized treatment is applied to the unstrengthened edges.

Claims

1. An apparatus comprising:

a first glass substrate having a first surface and a second surface, the second surface created by the separation of the substrate from a larger glass sheet, the first surface previously strengthened with a chemical treatment and the second surface not strengthened with a chemical treatment;

a second glass substrate having a third surface and a fourth surface, the fourth surface created by the separation of the substrate from the larger glass sheet, the third surface previously strengthened with a chemical treatment and the fourth surface not strengthened with a chemical treatment;

a first thin film including one or more conductive traces formed on the first surface of the first glass substrate prior to the separation of the first substrate from the larger sheet;

a second thin film including one or more conductive traces formed on the third surface of the second glass substrate prior to the separation of the second substrate from the larger sheet;

a first sealant applied to a perimeter area of the first surface and not applied on the conductive traces on the first surface; and

a second sealant applied to a perimeter area of the third surface and not applied on the conductive traces on the third surface,

wherein the first sealant is mated with the second sealant to removably seal the first surface with the third surface, and

wherein the first surface and the third surface are temporarily removably sealed when the first sealant on the first surface mates with the second sealant on the third surface such that the first sealant, the second sealant and the conductive traces occupy substantially all space between the first glass substrate and the second glass substrate.

2. The apparatus of claim 1, wherein the chemical treatment comprises an acid polish.

3. The apparatus of claim 1, wherein the chemical treatment comprises cerium oxide.

4. The apparatus of claim 1, wherein the chemical treatment comprises potassium nitrate.

5. The apparatus of claim 1, wherein the conductive traces include a thin film on conductor.

6. The apparatus of claim 5, wherein the thin film conductor includes one of indium tin oxide, amorphous silicon, copper indium diselenide, cadmium telluride, and film crystalline silicon.

7. The apparatus of claim 1, wherein the chemical treatment includes heating the first and third surface.

8. The apparatus of claim 1, wherein a passivation layer including one of silicon dioxide (SiO₂) and silicon nitride (SiNx) is formed over the one or more conductive traces prior to separation.

9. The apparatus of claim 1, wherein the glass substrate is separated from larger glass sheet by a separating mechanism including one of etching, laser scribing, mechanical scribing, and grinding and polishing, the second surface including a surface created by the separating mechanism.

10. The apparatus of claim 1, wherein the second surface includes one of a flat surface, a cylindrical surface, an uneven surface, and a surface including extended regions.

11. The apparatus of claim 1, wherein the sealant includes one of polymer film, polyimide, SU-8, photoresist, reworkable pressure sensitive adhesive, and silicone based adhesive.

12. An apparatus comprising:

a first glass substrate having a first surface and a second surface, the second surface created by the separation of the substrate from a larger glass sheet, the first surface previously strengthened with a chemical treatment;

a second glass substrate having a third surface and a fourth surface, the fourth surface created by the separation of the substrate from the larger glass sheet, the third surface previously strengthened with a chemical treatment;

a thin film including one or more conductive traces formed on the first surface of the first glass substrate and the third surface of the second glass substrate prior to the separation of the substrate from the larger sheet; and

a temporary removable sealant applied to a perimeter of the first surface and a perimeter of the third surface, wherein the first surface and the third surface are removably sealed when the temporary removable sealant on the first surface mates with the temporary removable sealant on the third surface such that the temporary removable sealant and the conductive traces occupy substantially all space between the first glass substrate and the second glass substrate.

13. The apparatus of claim 12, wherein the temporary removable sealant includes one of polymer film, polyimide, SU-8 photoresist, reworkable pressure sensitive adhesive, and silicone based adhesive.

14. The apparatus of claim 12, wherein the conductive traces include a thin film of conductor.

15. The apparatus of claim 12, wherein the temporary removable sealant is applied to entire perimeter areas of the first surface and the third surface surrounding the conductive traces.

16. An apparatus comprising:

a first glass substrate having a first surface and a second surface, the second surface created by the separation of the substrate from a larger glass sheet, the first surface previously strengthened with a chemical treatment;

a second glass substrate having a third surface and a fourth surface, the fourth surface created by the separation of the substrate from the larger glass sheet, the first surface previously strengthened with a chemical treatment;

a thin film including one or more conductive traces formed on the first surface of the first glass substrate and the third surface of the second glass substrate prior to the separation of the substrate from the larger sheet;

a temporary removable sealant applied to a perimeter of the first surface and a perimeter of the third surface, wherein the first surface and the third surface are removably sealed when the temporary removable sealant on the first surface mates with the temporary removable sealant on the third surface such that the temporary removable sealant and the conductive traces occupy substantially all space between the first glass substrate and the second glass substrate.

17. The apparatus of claim 16, wherein the temporary removable sealant includes one of polymer film, polymide, SU-8 photoresist, reworkable pressure sensitive adhesive, and silicone based adhesive.

18. The apparatus of claim 16, wherein the temporary removable sealant is applied to entire perimeter areas of the first surface and the third surface surrounding the conductive traces.