An improved OLED display includes a substrate, a semiconductor having a uniform thickness formed on the substrate, first and second ohmic contacts, and a driving voltage line having an input electrode and an output electrode. An insulating layer is formed on the driving voltage line and the output electrode. A control electrode is formed on the insulating layer and overlaps the semiconductor.The method of manufacturing the OLED display entails forming a semiconductor on a substrate, forming a photoresist film on the semiconductor, forming a doped amorphous silicon layer on the photoresist film, removing the photoresist film along with a portion of the doped amorphous silicon disposed on the photoresist film to form first and second ohmic contacts, respectively forming input and output electrodes on the first and second ohmic contacts, forming an insulating layer on the input and output electrodes, and forming a control electrode on the insulating layer.