SHAPING A COVER GLASS

• US 20090090694A1
• Filed: 02/12/2008
• Published: 04/09/2009
• Est. Priority Date: 10/03/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Clayton, Joseph Edward, Zhong, John J., Hotelling, Steve Porter
• Granted Patent: US 8,153,016 B2
• Time in Patent Office: Days
• US Class Current: 216/41
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality

Abstract

The fabrication of a touch sensor panel having co-planar single-layer touch sensors fabricated on the back side of a cover glass is disclosed. It can be desirable from a manufacturing perspective to perform all thin-film processing steps on a motherglass before separating it into separate parts. To perform thin-film processing on a motherglass before separation, a removable sacrificial layer such as a photoresist can be applied over the thin-film layers. Next, the motherglass can be scribed and separated, and grinding and polishing steps can be performed prior to removing the sacrificial layer. In alternative embodiments, after the protective sacrificial layer is applied, the bulk of the coverglass can be dry-etched using a very aggressive anisotropic etching that etches primarily in the z-direction. In this embodiment, the etching can be patterned using photolithography to create rounded corners or any other shape. The photoresist can then be removed.

Claims

1. A method of fabricating a plurality of touch sensor panels on one side of a substrate, comprising:

forming the plurality of touch sensor panels on one side of a substrate sheet;

applying a removable protective sacrificial layer over the touch sensor panels;

singulating the substrate sheet to separate the plurality of touch sensor panels; and

removing the protective sacrificial layer from each of the plurality of touch sensor panels.

2. The method of claim 1, further comprising forming each touch sensor panel as a plurality of co-planar single-layer touch sensors.

3. The method of claim 1, further comprising forming the plurality of touch sensor panels using thin-film processing.

4. The method of claim 1, wherein the substrate is a cover glass and the substrate sheet is a mother glass.

5. The method of claim 1, further comprising applying photoresist as the removable protective sacrificial layer.

6. The method of claim 1, further comprising singulating the substrate sheet using scribe and break techniques.

7. The method of claim 1, further comprising performing grinding and polishing the separated touch sensor panels prior to removing the sacrificial layer.

8. The method of claim 1, further comprising singulating the substrate sheet using dry-etching techniques.

9. The method of claim 1, further comprising forming a step in the substrate supporting each of the touch sensor panels prior to singulating the substrate sheet.

10. The method of claim 9, further comprising forming the step using etching techniques.

11. The method of claim 1, further comprising forming radiused corners in the substrate supporting each of the touch sensor panels prior to forming the touch sensor panels.

12. The method of claim 11, further comprising forming the radiused corners using etching techniques.

13. A plurality of co-planar single-layer touch sensor panels fabricated on one side of a substrate, each touch sensor panel having a plurality of touch sensors formed from columns and adjacent patches of conductive material on a same layer of the substrate, the plurality of touch sensor panels formed by a process comprising:

forming the columns and patches for each of the plurality of touch sensor panels on one side of a substrate sheet;

applying a removable protective sacrificial layer over the touch sensor panels;

singulating the substrate sheet to separate the plurality of touch sensor panels; and

removing the protective sacrificial layer from each of the plurality of touch sensor panels.

14. The plurality of touch sensor panels formed by the process of claim 13, the process further comprising forming each touch sensor panel as a plurality of co-planar single-layer touch sensors.

15. The plurality of touch sensor panels formed by the process of claim 13, the process further comprising forming the plurality of touch sensor panels using thin-film processing.

16. The plurality of touch sensor panels formed by the process of claim 13, wherein the substrate is a cover glass and the substrate sheet is a mother glass.

17. The plurality of touch sensor panels formed by the process of claim 13, the process further comprising applying photoresist as the removable protective sacrificial layer.

18. The plurality of touch sensor panels formed by the process of claim 13, the process further comprising singulating the substrate sheet using scribe and break techniques.

19. The plurality of touch sensor panels formed by the process of claim 13, the process further comprising performing grinding and polishing the separated touch sensor panels prior to removing the sacrificial layer.

20. The plurality of touch sensor panels formed by the process of claim 13, the process further comprising singulating the substrate sheet using dry-etching techniques.

21. The plurality of touch sensor panels formed by the process of claim 13, the process further comprising forming radiused corners in the substrate supporting each of the touch sensor panels prior to forming the touch sensor panels.

23. A plurality of co-planar single-layer touch sensor panels fabricated on one side of a substrate, each touch sensor panel having a plurality of touch sensors formed from columns and adjacent patches of conductive material on a same layer of the substrate, the plurality of touch sensor panels formed by a process comprising:

forming a step in the substrate to define each of the plurality of touch sensor panels;

forming the columns and patches for each of the plurality of touch sensor panels on one side of a substrate sheet; and

singulating the substrate sheet to separate the plurality of touch sensor panels.

22. The plurality of touch sensor panels formed by the process of claim 23, the process further comprising forming the radiused corners using etching techniques.

24. The plurality of touch sensor panels formed by the process of claim 23, the process further comprising forming the step using etching techniques.