Display apparatus and method of manufacturing the same

1. A display apparatus comprising:

a substrate comprising a first surface, a second surface opposite the first surface, a display area defined on the first surface, and a non-display area defined on the second surface;

a plurality of display elements at the display area on the first surface of the substrate;

a driving circuit on the second surface and overlapping with the display area of the substrate;

a first conductive pattern on the second surface of the substrate; and

a second conductive pattern on the first surface of the substrate and connected to the first conductive pattern via a contact hole extending through the substrate,

wherein a surface roughness of the second surface of the substrate is greater than a surface roughness of the first surface of the substrate.

2. The display apparatus of claim 1 , wherein a material component of the first surface is different from a material component of the second surface.

3. The display apparatus of claim 1 , wherein the first conductive pattern is buried within the substrate.

4. The display apparatus of claim 3 , wherein:

the first conductive pattern includes a surface, another surface opposite the surface, and a side surface extending between the surface and the other surface to connect the surface to the other surface;

the surface of the first conductive pattern is located on a same plane as that of the first surface of the substrate; and

the other surface and the side surface of the first conductive pattern are in direct contact with the substrate.

5. The display apparatus of claim 1 , wherein the substrate comprises a first base layer and a second base layer on the first base layer, and

the display apparatus further comprises a connection pattern arranged between the first base layer and the second base layer, and electrically connecting the first conductive pattern to the second conductive pattern.

6. The display apparatus of claim 5 , wherein the first conductive pattern is connected to the connection pattern via a first contact hole in the first base layer, and

the connection pattern is connected to the second conductive pattern via a second contact hole in the second base layer.

7. The display apparatus of claim 1 , further comprising an electronic structure on the second surface, and electrically connected to the first conductive pattern to overlap with the display area.

8. The display apparatus of claim 1 , further comprising a plurality of first signal lines extending in a first direction and a plurality of second signal lines extending in a second direction crossing the first direction at the display area,

wherein the second conductive pattern is connected to the plurality of first signal lines or the plurality of second signal lines.

9. The display apparatus of claim 8 , further comprising a plurality of pixel circuits at the display area, and connected to the plurality of display elements, respectively, each of the plurality of pixel circuits comprising:

a thin-film transistor comprising a semiconductor layer, a gate electrode at least partially overlapping with the semiconductor layer, and an electrode layer connected to the semiconductor layer; and

a storage capacitor comprising a lower electrode corresponding to at least a portion of the gate electrode, and an upper electrode on the lower electrode,

wherein the second conductive pattern comprises a same material as a material of that of at least one selected from among the gate electrode, the electrode layer, the lower electrode, and the upper electrode.

10. The display apparatus of claim 8 , wherein the plurality of second signal lines are electrically connected to the driving circuit via the second conductive pattern.

11. The display apparatus of claim 1 , further comprising a power supply line on the second surface overlapping with the display area of the substrate.