Patent ID: 7501756

Claim:
An organic light emitting display, comprising: a TFT substrate comprising an insulating substrate, a semiconductor layer having a source region and a drain region, a first insulating layer having holes that expose a portion of the source region and the drain region and a thin film transistor having a source electrode connected to the source region and a drain electrode connected to the drain region through the holes; a lower electrode formed on the first insulating layer and formed by extending one of the source electrode and the drain electrode; a second insulating layer having a first opening that exposes a first portion of the lower electrode; a third insulating layer having a second opening that exposes a second portion of the lower electrode, said second portion of the lower electrode being within the first portion of the lower electrode; an organic thin film layer formed on the third insulating layer and the second portion of the lower electrode; and an upper electrode formed on the organic thin film layer: wherein the third insulating layer has a taper angle not greater than 40° at an edge of the second opening, and a step height between the upper surface of the lower electrode at the second opening and the bottom surface of the organic thin film layer formed on the third insulating layer is less than or equal to 3,000 Å.