Touch display substrate, fabrication method and touch display device

1. A touch display substrate, comprising:

a base substrate;

a conductive bridge and a touch-control signal lead over the base substrate, wherein the touch-control signal lead is in contact with a first surface portion of the conductive bridge;

a passivation layer over the touch-control signal lead and the conductive bridge, wherein the passivation layer includes a via-hole to expose a second surface portion of the conductive bridge;

a touch electrode over the passivation layer and being connected to the conductive bridge through the via-hole;

gate lines;

data lines;

a thin film transistor; and

a pixel electrode,

wherein:

the gate lines and the data lines define a pixel cell;

the thin film transistor and the pixel electrode are located in the pixel cell;

the pixel electrode is located under a drain electrode of the thin film transistor;

orthographic projection of the conductive bridge on the substrate has no overlapping with orthographic projection of the gate lines on the substrate; and

the first surface portion of the conductive bridge is electrically connected to the second surface portion of the conductive bridge.

2. The touch display substrate of claim 1 , wherein projections of the via-hole and the touch-control signal lead on the base substrate do not overlap with one another.

3. The touch display substrate of claim 2 , wherein:

the first surface portion of the conductive bridge is sandwiched between the touch-control signal lead and the base substrate.

4. The touch display substrate of claim 2 , wherein:

the touch-control signal lead is sandwiched between the first surface portion of the conductive bridge and the base substrate.

5. The touch display substrate of claim 1 , wherein projections of the via-hole and the touch-control signal lead on the base substrate overlap with one another, and the touch-control signal lead is sandwiched between the conductive bridge and the base substrate.

6. The touch display substrate of claim 2 , wherein a closest distance between adjacent ends of the touch-control signal lead and the via-hole through the passivation layer is about 4 μm or greater in a direction along a surface of the base substrate.

7. The touch display substrate of claim 1 , wherein the touch-control signal lead includes one or more of:

a first conductive material pattern made of at least an oxidation resistant conductive material,

a second conductive material pattern made of at least a low resistance conductive material, and

a third conductive material pattern made of at least an oxidation resistant conductive material.

8. The touch display substrate of claim 7 , wherein the second conductive material pattern is sandwiched between the first and third conductive material patterns.

9. The touch display substrate of claim 1 , wherein:

the conductive bridge and the touch-control signal lead are disposed over a first surface portion of the base substrate,

the pixel electrode is disposed over a second surface portion of the base substrate, and

the data lines, the source electrode, and the drain electrode of the thin film transistor are disposed over a third surface portion of the base substrate.

10. The touch display substrate of claim 1 , wherein the conductive bridge is in a strip shape and with at least a portion containing the first surface portion configured in parallel with the touch-control signal lead.

11. A touch display device, comprising the touch display substrate of claim 1 .

12. A method of fabricating a touch display substrate, comprising:

forming a conductive bridge and a touch-control signal lead over a base substrate, wherein the touch-control signal lead is in contact with a first surface portion of the conductive bridge;

forming a passivation layer over the touch-control signal lead and the conductive bridge, wherein the passivation layer includes a via-hole to expose a second surface portion of the conductive bridge;

forming a touch electrode over the passivation layer and being connected to the conductive bridge through the via-hole; and

forming gate lines, data lines, a thin film transistor, and a pixel electrode over the base substrate, wherein:

the gate lines and the data lines define a pixel cell;

the thin film transistor and the pixel electrode are located in the pixel cell;

the pixel electrode is located under a drain electrode of the thin film transistor;

orthographic projection of the conductive bridge on the substrate has no overlapping with orthographic projection of the gate lines on the substrate; and

the first surface portion of the conductive bridge is electrically connected to the second surface portion of the conductive bridge.

13. The method of claim 12 , wherein projections of the via-hole and the touch-control signal lead on the base substrate do not overlap with one another, and a closest distance between adjacent ends of the touch-control signal lead and the via-hole through the passivation layer is about 4 μm or greater in a direction along a surface of the base substrate.

14. The method of claim 13 , wherein:

the first surface portion of the conductive bridge is sandwiched between the touch-control signal lead and the base substrate, or the touch-control signal lead is sandwiched between the first surface portion of the conductive bridge and the base substrate.

15. The method of claim 12 , wherein:

projections of the via-hole and the touch-control signal lead on the base substrate overlap with one another, and

the touch-control signal lead is sandwiched between the conductive bridge and the base substrate.

16. The method of claim 12 , further including:

forming the gate lines and a gate electrode simultaneously on the base substrate in a single process;

forming an insulating layer on the gate lines and the gate electrode;

forming an active layer on the insulating layer by using a patterning process;

forming the pixel electrode on the insulating layer by using a patterning process;

forming the conductive bridge or the touch-control signal lead on the insulating layer over the base substrate;

forming data lines on the insulating layer by using a patterning process; and

forming a source electrode and a drain electrode on the active layer to connect the active layer with the pixel electrode.

17. The method of claim 12 , wherein the pixel electrode and the conductive bridge are simultaneously formed in a single process.

18. The method of claim 12 , wherein the touch-control signal lead, the data lines, the source electrode, and the drain electrode are simultaneously formed in a single process.