Display substrate and method of manufacturing the same

1. A display substrate comprising:

a substrate comprising a display area and a peripheral area;

a pixel part on the display area, the pixel part comprising a switching element, and a pixel electrode electrically connected to the switching element;

a pad part on the peripheral area and contacting a terminal of an external device, the pad part comprising:

a pad electrode and a contact electrode,

the pad electrode comprising a first metal layer, and a second metal layer on the first metal layer,

the contact electrode contacting the second metal layer; and

a sacrificial electrode on the peripheral area, spaced apart from the pad electrode of the pad part, and comprising an exposed portion including:

a first portion contacting the contact electrode, and

a second portion exposed to an external side of the display substrate.

2. The display substrate of claim 1 , wherein the contact electrode includes a same material as the pixel electrode.

3. The display substrate of claim 1 , wherein a standard reduction potential of the sacrificial electrode is lower than a standard reduction potential of the contact electrode.

4. The display substrate of claim 1 , wherein the exposed portion of the sacrificial electrode includes a first metal layer which is in a same layer as the first metal layer of the pad electrode and contacts the contact electrode.

5. The display substrate of claim 4 , wherein

the first metal layers include aluminum (Al),

the second metal layer includes molybdenum (Mo), and

the contact electrode includes a same material as the pixel electrode.

6. The display substrate of claim 5 , wherein the contact electrode includes indium (In).

7. The display substrate of claim 4 , wherein

the first metal layers include titanium (Ti),

the second metal layer includes copper (Cu), and

the contact electrode includes indium (In).

8. The display substrate of claim 1 ,

wherein the exposed portion of the sacrificial electrode includes a third metal layer different from the first and second metal layers, the third metal layer contacting the contact electrode, and

further comprising a first signal line, and a second signal line crossing the first signal line on the display area, the second signal line extended from the pad electrode on the peripheral area and including the third metal layer.

9. The display substrate of claim 8 , wherein

the first metal layer includes titanium (Ti),

the second metal layer includes copper (Cu), and

the third metal layer includes aluminum (Al).

10. The display substrate of claim 1 , further comprising:

the pad electrode and the sacrificial electrode on a substrate, and

an insulation layer on the substrate and including an opening portion partially exposing the sacrificial electrode,

wherein the contact electrode contacts the sacrificial electrode through the opening portion, and the exposed portion of the sacrificial electrode is exposed through the opening portion of the insulation layer.

11. The display substrate of claim 1 ,

further comprising a signal line connected to a gate electrode of the switching element on the display area,

wherein the pad electrode on the peripheral area is extended from a first terminal of the signal line.

12. The display substrate of claim 1 ,

further comprising a signal line connected to a source electrode of the switching element on the display area,

wherein the pad electrode on the peripheral area is extended from a first terminal of the signal line.

13. The display substrate of claim 1 , further comprising:

a gate drive circuit on the peripheral area, adjacent to first terminals of signal lines on the display area, wherein the gate drive circuit sequentially outputs a plurality of gate signals.

14. The display substrate of claim 13 ,

further comprising a driving line delivering a control signal to the gate drive circuit,

wherein the pad electrode on the peripheral area is extended from a first terminal of the driving line.

15. The display substrate of claim 14 , wherein the driving line is a clock signal line delivering a clock signal to the gate drive circuit.