Touch sensor panel with reduced dimensions and cross-coupling
Disclosed herein is a touch sensor panel that includes a substrate that includes a bending portion, and a plurality of electrodes formed in a first layer on a first surface of the substrate, the plurality of electrodes forming first electrodes and second electrodes and the plurality of electrodes defining an active area for touch sensing. The touch sensor panel further includes a plurality of routing traces formed in the first layer on the first surface of the substrate in a border area outside the active area and formed from the first material (copper), a plurality of bridges formed in a second layer, the plurality of bridges connecting groups of the plurality of electrodes to form the first electrodes and formed from a second material (silver), and sensing circuitry connected to the substrate and to the plurality of routing traces at a location after the bending portion.
1. A touch sensor panel including:
a substrate;
a plurality of electrodes formed in a first layer on a first surface of the substrate from a first material, the plurality of electrodes forming first electrodes and second electrodes and the plurality of electrodes defining an active area for touch sensing;
a plurality of routing traces formed in the first layer on the first surface of the substrate in a border area outside the active area, the plurality of routing traces formed from the first material, wherein the first material includes copper; and
a plurality of bridges and one or more shield electrodes formed in a second layer, different from the first layer, wherein:
the plurality of bridges connect groups of the plurality of electrodes to form the first electrodes,
the plurality of bridges and the one or more shield electrodes are formed from a second material different than the first material, wherein
the second material includes silver,
the one or more shield electrodes positioned above the plurality of routing traces in the border area, and
the first layer is between the second layer and the first surface of the substrate.
2. The touch sensor panel of claim 1 , wherein each routing trace of the plurality of routing traces has a width between 10 microns and 25 microns.
3. The touch sensor panel of claim 1 , wherein each routing trace of the plurality of routing traces is spaced apart from another routing trace of the plurality of routing traces by between 10 microns and 25 microns.
4. The touch sensor panel of claim 1 , wherein the border area has a width less than 2 millimeters.
5. The touch sensor panel of claim 1 , wherein a height of the touch sensor panel is less than 50 micron.
6. The touch sensor panel of claim 1 , wherein the one or more shield electrodes reduce parasitic coupling.
7. The touch sensor panel of claim 1 , wherein the substrate is formed from a flexible material and includes a bending portion.
8. The touch sensor panel of claim 7 , further comprising:
sensing circuitry connected to the substrate and connected to the plurality of routing traces at a location after the bending portion of the substrate.
9. The touch sensor panel of claim 7 , wherein the flexible material is polyethylene terephthalate.
10. The touch sensor panel of claim 1 , wherein the substrate is less than 25 microns.
11. The touch sensor panel of claim 1 , wherein the plurality of electrodes is patterned by a wet etching process.
12. The touch sensor panel of claim 1 , further comprising an insulator layer between the first layer and the second layer.
13. The touch sensor panel of claim 12 , wherein the insulator layer is between 1 micron and 2 microns.
14. The touch sensor panel of claim 1 , wherein:
the first electrodes have a first comb structure; and
the second electrodes have a second comb structure such that a plurality of the first electrodes and a plurality of the second electrodes interlock.
15. The touch sensor panel of claim 1 , wherein
a bridge of the plurality of bridges between a first electrode of the plurality of electrodes and a second electrode of the plurality of electrodes is connected to the first electrode by a via to a center of the first electrode and connected to the second electrode by a via to a center of the second electrode.
16. An electronic device including:
an energy storage device;
wireless communication circuitry;
a display; and
a touch sensor panel comprising:
a substrate,
a plurality of electrodes formed in a first layer on a first surface of the substrate from a first material, the plurality of electrodes forming first electrodes and second electrodes and the plurality of electrodes defining an active area for touch sensing,
a plurality of routing traces formed in the first layer on the first surface of the substrate in a border area outside the active area, the plurality of routing traces formed from the first material, wherein the first material includes copper, and
a plurality of bridges and one or more shield electrodes formed in a second layer, different from the first layer, wherein:
the plurality of bridges connect groups of the plurality of electrodes to form the first electrodes,
the plurality of bridges and the one or more shield electrodes are formed from a second material different than the first material,
the second material includes silver,
the one or more shield electrodes are positioned above the plurality of routing traces in the border area, and
the first layer is between the second layer and the first surface of the substrate.
17. The electronic device of claim 16 , wherein each routing trace of the plurality of routing traces has a width between 10 microns and 25 microns.
18. The electronic device of claim 16 , wherein each routing trace of the plurality of routing traces is spaced apart from another routing trace of the plurality of routing traces by between 10 microns and 25 microns.
19. The electronic device of claim 16 , wherein the border area has a width less than 2 millimeters.
20. The electronic device of claim 16 , wherein a height of the touch sensor panel is less than 50 micron.