Display substrate, method of manufacturing the same and display device having the same

A display device having a display area and one or more peripheral areas and comprising a first substrate and a second substrate, the first substrate comprising:

• a pixel transistor disposed on a first substrate in the display area;
• an integrated driving circuit disposed in at least one of the peripheral areas, the integrated driving circuit comprising a transistor part, a first wiring part extending in a first direction and electrically connected to the transistor part, and a second wiring part extending in a second direction to cross the first wiring part and electrically connected to the transistor part, where the second wiring part is disposed above the first wiring part;
• an insulation layer disposed between the first wiring part and the second wiring part;
• a protection layer disposed on the second wiring part;
• a separation maintaining part disposed in the display area to maintain a gap between the first substrate and the second substrate;
• and
• a buffer layer disposed over the protection layer, the buffer layer covering the transistor part and at least an area where the second wiring part crosses the first wiring part, and comprising a same material as the separation maintain part.