Capacitive touch screen sensor and corresponding method of fabrication

• US 9,898,151 B2
• Filed: 02/06/2013
• Issued: 02/20/2018
• Est. Priority Date: 02/06/2013
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Sebastian, Muthu, Travasso, Dominic M., Swartz, Steven T.
• Primary Examiner(s): McLoone, Peter D
• Application Number:
  US14/760,769
• Publication Number:
  US 20150363022A1
• Time in Patent Office: 1,840 Days
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 2203/04112 Electrode mesh in capacitive digitiser: electrode for touch sensing is formed of a mesh of very fine, normally metallic, interconnected lines that are almost invisible to see. This provides a quite large but transparent electrode surface, without need for ITO or similar transparent conductive material
• 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: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

A capacitive touch screen sensor 104 is disclosed. The sensor 104 comprises an array of drive electrodes 100, an array of sense electrodes 102 separated from the array of drive electrodes by a dielectric layer 200, each sense electrode 102 being offset from each drive electrode 100 to define respective overlapping regions 112 and first non-overlapping regions 113, and a plurality of non-electrically connected electrodes 402, each non-electrically connected electrode 402 being arranged to correspond to each first non-overlapping region 113 and spaced from adjacent drive 100 or sense electrodes 102 by a perimeter gap 404. The perimeter gap 404 may have a width of about 100 um or less. A related touch panel and method of fabricating the same are also disclosed.

Claims

1. A capacitive touch screen sensor comprising:

(i) an array of drive electrodes;

(ii) an array of sense electrodes separated from the array of drive electrodes by a dielectric layer, each sense electrode being offset from each drive electrode to define respective overlapping regions and first non-overlapping regions, the drive electrodes not overlapping with the first non-overlapping regions and the sense electrodes not overlapping with the first non-overlapping regions, each drive electrode comprising a plurality of first conductive pads, each sense electrode comprising a plurality of second conductive pads, the first and second conductive pads having a substantially same shape and size; and

(iii) a plurality of non-electrically connected electrodes within the first non-overlapping regions, each non-electrically connected electrode being arranged to correspond to each first non-overlapping region and spaced from adjacent drive or sense electrodes by a perimeter gap, wherein the perimeter gap has a width of about 100 micrometers or less,

wherein each non-electrically connected electrode has a generally X-shape, wherein the perimeter gap is configured to space the generally X-shape non-electrically connected electrodes from adjacent drive or sense electrodes, and

wherein each non-electrically connected electrode comprises a plurality of elongate gaps dividing the non-electrically connected electrode into smaller portions and defining a mesh pattern.

2. A capacitive touch screen sensor according to claim 1, wherein the width is between 20 micrometers and 100 micrometers.

3. A capacitive touch screen sensor according to claim 1, wherein the width is about 30 micrometers.

4. A capacitive touch screen sensor according to claim 1, wherein the array of drive electrodes and the array of sense electrodes are arranged on opposing first and second surfaces of a same substrate.

5. A capacitive touch screen sensor according to claim 4, wherein the plurality of non-electrically connected electrodes is arranged on one of the opposing surfaces.

6. A capacitive touch screen sensor according to claim 5, wherein the plurality of non-electrically connected electrodes is arranged on the same surface as the array of drive electrodes, and further comprising at least one supplemental non-electrically connected electrode portion which is in a second non-overlapping region and in registration with corresponding sense electrodes.

7. A capacitive touch screen sensor according to claim 5, wherein the plurality of non-electrically connected electrodes is arranged on the same surface as the array of sense electrodes, and further comprising at least one supplemental non-electrically connected electrode portion which is in a second non-overlapping region and in registration with a corresponding drive electrode.

8. A capacitive touch screen sensor according to claim 4, wherein the plurality of non-electrically connected electrodes is arranged on both of the opposing surfaces.

9. A capacitive touch screen sensor according to claim 1, wherein the array of drive electrodes and the array of sense electrodes are arranged on surfaces of different substrates.

10. A capacitive touch screen sensor according to claim 9, wherein the plurality of non-electrically connected electrodes is arranged on one of the surfaces.

11. A capacitive touch screen sensor according to claim 10, wherein the plurality of non-electrically connected electrodes is arranged on the same surface as the array of drive electrodes and further comprising at least one supplemental non-electrically connected electrode portion which is in a second non-overlapping region and in registration with a corresponding sense electrode.

12. A capacitive touch screen sensor according to claim 10, wherein the plurality of non-electrically connected electrodes is arranged on the same surface as the array of sense electrodes, and further comprising at least one supplemental non-electrically connected electrode portion which is in a second non-overlapping region and in registration with a corresponding drive electrode.

13. A capacitive touch screen sensor according to claim 9, wherein the plurality of non-electrically connected electrodes is arranged on both of the surfaces.

14. A capacitive touch screen sensor according to claim 1, wherein the drive and sense electrodes and the non-electrically connected electrodes comprise one or more of Zinc Oxide (ZnO), Tin(II) Oxide (SnO), Indium Oxide (InO), Indium Zinc Oxide (IZO), Graphene, and Indium Tin Oxide (ITO).

15. A capacitive touch screen sensor according to claim 1, wherein separation distance between the array of drive electrodes and the array of sense electrodes is about 50 micrometers to 175 micrometers.

16. A capacitive touch sensitive device, comprising the capacitive touch screen sensor of claim 1.

17. A method of fabricating a capacitive touch screen sensor, comprising:

(i) forming an array of drive electrodes;

(ii) forming an array of sense electrodes separated from the array of drive electrodes by a dielectric layer, each sense electrode being offset from each drive electrode to define respective overlapping regions and first non-overlapping regions, the drive electrodes not overlapping with the first non-overlapping regions and the sense electrodes not overlapping with the first non-overlapping regions, each drive electrode comprising a plurality of first conductive pads, each sense electrode comprising a plurality of second conductive pads, the first and second conductive pads having a substantially same shape and size; and

(iii) forming a plurality of non-electrically connected electrodes within the first non-overlapping regions with each non-electrically connected electrode arranged to correspond to each first non-overlapping region and spaced from adjacent drive or sense electrodes by a perimeter gap;

wherein the perimeter gap has a width of about 100 micrometers or less, wherein each non-electrically connected electrode has a generally X-shape, wherein the perimeter gap is configured to space the generally X-shape non-electrically connected electrodes from adjacent drive or sense electrodes, and wherein each non-electrically connected electrode comprises a plurality of elongate gaps dividing the non-electrically connected electrode into smaller portions and defining a mesh pattern.

18. A capacitive touch screen sensor comprising:

(i) an array of first electrodes disposed on a first surface;

(ii) an array of second electrodes separated from the array of first electrodes by a dielectric layer, the array of second electrodes being disposed on a different second surface, each second electrode being offset from each first electrode to define respective overlapping regions and first non-overlapping regions, the first electrodes not overlapping with the first non-overlapping regions and the second electrodes not overlapping with the first non-overlapping regions, each first electrode comprising a plurality of first conductive pads, each second electrode comprising a plurality of second conductive pads, the first and second conductive pads having a substantially same shape and size; and

(iii) a plurality of non-electrically connected electrodes within the first non-overlapping regions, the plurality of non-electrically connected electrodes disposed on the first surface, each non-electrically connected electrode being arranged to correspond to each first non-overlapping region and spaced from adjacent first or second electrodes by a perimeter gap, wherein the perimeter gap has a width of about 100 micrometers or less,

wherein each non-electrically connected electrode is continuous and has a generally X-shape.

19. The capacitive touch screen sensor of claim 18 further comprising at least one supplemental non-electrically connected electrode portion disposed on the first surface and separated from adjacent first electrodes, each supplemental non-electrically connected electrode portion being in registration with and overlapping a second electrode in the plurality of second electrodes.

20. The capacitive touch screen sensor of claim 18, wherein the first and second surfaces are surfaces of different substrates.

21. The capacitive touch screen sensor of claim 18, wherein the first and second surfaces are opposing surfaces of a same substrate.

22. A capacitive touch sensitive device, comprising the capacitive touch screen sensor of claim 18.