Full perimeter chemical strengthening of substrates

• US 7,810,355 B2
• Filed: 06/30/2008
• Issued: 10/12/2010
• Est. Priority Date: 06/30/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Zhong, John Z., Feinstein, Casey J.
• Primary Examiner(s): Lazorcik; Jason L
• Assistant Examiner(s): SNELTING, ERIN LYNN
• Application Number:
  US12/165,336
• Publication Number:
  US 20090324899A1
• Time in Patent Office: 834 Days
• Field of Search: 65/301.4, 65/301, 65/31, 651/05, 216/20, 216/83, 216/97
• US Class Current: 65/30.1
• 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. A method for strengthening glass sheets including conductive traces formed thereon, comprising:

positioning a first glass sheet including a first thin film formed thereon, the first thin film including a first set of conductive traces and having a top surface and a perimeter, and a second glass sheet including a second thin film formed thereon, the second thin film including a second set of conductive traces and having a top surface and a perimeter, such that the top surface of the first thin film faces the top surface of the second thin film;

sealing the first glass sheet to the second glass sheet with a sealant around the perimeters of the first and second thin films without applying the sealant to the top surfaces;

applying a strengthening treatment to an untreated region of at least one of the first glass sheet and the second glass sheet; and

separating the first and second glass sheets after the strengthening treatment has been applied.

2. The method of claim 1, further comprising:

forming the first and the second set of conductive traces on a mother sheet of glass; and

separating the mother sheet into at least a first portion and a second portion, the first portion including the first glass sheet and the second portion including the second glass sheet.

3. The method of claim 2, further comprising,

chemically strengthening the mother sheet prior to forming the first and the second set of conductive traces.

4. The method of claim 2, wherein separating the mother sheet into at least the first portion and the second portion includes scribing the mother sheet with a laser.

5. The method of claim 2, wherein separating the mother sheet into at least the first portion and the second portion includes etching the mother sheet.

6. The method of claim 2, wherein separating the mother sheet into at least the first portion and the second portion includes applying a process of glass machining to the mother sheet.

7. The method of claim 1, wherein at least one of the first and second thin films includes indium tin oxide.

8. The method of claim 1, wherein the first thin film and the second thin film include a protective layer.

9. The method of claim 1, wherein the sealing includes clamping the first glass sheet and the second glass sheet together with a ring.

10. The method of claim 1, wherein the applying of the strengthening treatment to the untreated region of at least one of the first glass sheet and the second glass sheet includes applying an edge polish to the untreated region.

11. The method of claim 1, wherein the applying of the strengthening treatment to the untreated region of at least one of the first glass sheet and the second glass sheet includes applying a chemical etch to the untreated region.

12. The method of claim 1, wherein the applying of the strengthening treatment to the untreated region of at least one of the first glass sheet and the second glass sheet includes applying an acid polish to the untreated region.

13. The method of claim 1, wherein the applying of the strengthening treatment to the untreated region of at least one of the first glass sheet and the second glass sheet includes immersing the first and second glass sheets into a chemical strengthener.

14. The method of claim 1, wherein the applying of the strengthening treatment to the untreated region of at least one of the first glass sheet and the second glass sheet includes applying a localized strengthening treatment to the untreated regions of the first and second glass sheets.

15. The method of claim 1, wherein the sealing includes applying a first sealant around the perimeter of the first thin film and applying a second sealant around the perimeter of the second thin film.