Dielectric layer for touch sensor stack

• US 9,116,584 B2
• Filed: 07/24/2012
• Issued: 08/25/2015
• Est. Priority Date: 07/24/2012
• Status: Active Grant

• Current Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Original Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Inventors: Trend, Matthew, GUARD, David Brent
• Primary Examiner(s): GIESY, ADAM
• Application Number:
  US13/556,805
• Publication Number:
  US 20140028569A1
• Time in Patent Office: 1,127 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

In one embodiment, a touch sensor includes a substrate comprising a first surface. The touch sensor further includes a plurality of first electrodes comprising one or more conductive materials on the first surface. The touch sensor further includes a dielectric layer formed over the first electrodes and at least a portion of the first surface. The dielectric layer has a dielectric constant less than or equal to approximately 3.

Claims

1. A touch sensor comprising:

a substrate comprising a first surface configured to face toward an electronic display panel when coupled to the electronic display panel;

a plurality of first electrodes comprising one or more conductive materials on the first surface; and

a dielectric layer formed over the first electrodes and at least a portion of the first surface, the dielectric layer having a dielectric constant less than or equal to approximately 3 and being configured to face toward the electronic display panel when coupled to the electronic display panel.

2. The touch sensor of claim 1, wherein the dielectric layer is configured to face the electronic display panel with an air gap between the dielectric layer and the electronic display panel.

3. The touch sensor of claim 1, wherein the dielectric layer is in at least indirect contact with an electronic display panel.

4. The touch sensor of claim 1, wherein there is no adhesive layer between the dielectric layer and the first electrodes.

5. The touch sensor of claim 1, further comprising:

a plurality of second electrodes comprising one or more conductive materials on a second surface of the first substrate or a second substrate;

a second dielectric layer formed on the second electrodes and at least a portion of the second surface; and

a substantially transparent cover panel disposed on the dielectric layer.

6. The touch sensor of claim 1, wherein the conductive materials comprise indium tin oxide, a plurality of fine lines of metal, or a plurality of carbon nanotubes.

7. The touch sensor of claim 1, wherein the dielectric constant of the dielectric layer is less than approximately 2 and greater than approximately 1.

8. The touch sensor of claim 1, wherein the dielectric constant of the dielectric layer is less than approximately 3 and greater than approximately 2.

9. A device comprising:

a touch sensor comprising;

a substrate comprising a first surface configured to face toward an electronic display panel when coupled to the electronic display panel;

a plurality of first electrodes comprising one or more conductive materials on the first surface; and

a dielectric layer formed over the first electrodes and at least a portion of the first surface, the dielectric layer having a dielectric constant less than or equal to approximately 3 and being configured to face toward the electronic display panel when coupled to the electronic display panel; and

one or more computer-readable non-transitory storage media coupled to the touch sensor and embodying logic that is configured when executed to control the touch sensor.

10. The device of claim 9, wherein the dielectric layer is configured to face the electronic display panel with an air gap between the dielectric layer and the electronic display panel.

11. The device of claim 9, wherein the dielectric layer is in at least indirect contact with an electronic display panel.

12. The device of claim 9, wherein there is no adhesive layer between the dielectric layer and the first electrodes.

13. The device of claim 9, wherein the touch sensor further comprises:

a plurality of second electrodes comprising one or more conductive materials on a second surface of the first substrate or a second substrate;

a second dielectric layer formed on the second electrodes and at least a portion of the second surface; and

a substantially transparent cover panel disposed on the dielectric layer.

14. The device of claim 9, wherein the conductive materials comprise indium tin oxide, a plurality of fine lines of metal, or a plurality of carbon nanotubes.

15. The device of claim 9, wherein the dielectric constant of the dielectric layer is less than approximately 2 and greater than approximately 1.

16. The device of claim 9, wherein the dielectric constant of the dielectric layer is less than approximately 3 and greater than approximately 2.

17. A method for forming a touch sensor, the method comprising:

providing a substrate comprising a first surface configured to face toward an electronic display panel when coupled to the electronic display panel;

forming a plurality of first electrodes comprising one or more conductive materials on the first surface; and

forming a dielectric layer on the first electrodes and at least a portion of the first surface, the dielectric layer having a dielectric constant less than or equal to approximately 3 and being configured to face toward the electronic display panel when coupled to the electronic display panel.

18. The method of claim 17, further comprising attaching the electronic display panel to the substrate such that the electronic display panel faces the dielectric layer, with an air gap disposed between the dielectric layer and the electronic display panel.

19. The method of claim 17, further comprising attaching an electronic display panel to the substrate such that the dielectric layer is in at least indirect contact with the electronic display panel.

20. The method of claim 17, wherein the dielectric constant of the dielectric layer is less than approximately 2 and greater than approximately 1.