Patent ID: 8212247

Claim:
An organic light emitting display, comprising: source/drain electrodes of a first thin film transistor (TFT) and a gate electrode of a second TFT on a substrate; a first insulation layer on the source/drain electrodes of the first TFT and on the gate electrode of the second TFT, the first insulation layer including a first via hole therethrough exposing portions of the source/drain electrodes of the first TFT; first and second oxide semiconductor layers on the first insulation layer, the first and second oxide semiconductor layers overlapping the source/drain electrodes of the first TFT and the gate electrode of the second TFT, respectively; a second insulation layer on the first and second oxide semiconductor layers, the second insulation layer including a second via hole therethrough exposing a portion of the second oxide semiconductor layer; a gate electrode on the second insulation layer, the gate electrode overlapping the first oxide semiconductor layer of the first TFT; and source/drain electrodes on the second insulation layer to contact the second oxide semiconductor layer through the second via hole.