ORGANIC EL DISPLAY DEVICE

The present invention provides an organic EL display device using a top gate structure of an oxide semiconductor. The organic EL display device further reduces the resistance to moisture while reducing the resistance of the contact regions. A thin film transistor element substrate 1 of the organic EL display device includes a first moisture barrier layer 6 covering the gate insulating layer 4 andthe gate electrode 5, covering the contact regions 3a1,3a2 of the oxide semiconductor layer 3 other than the connecting portion of the contact region 3a1 connected to the source electrode 8 and the connecting portion of the contact region connected to the drain electrode 9, and covering an surface of the substrate 2 on which the oxide semiconductor layer 3 is not disposed. The first moisture barrier layer 6 includes a metal oxide and is formed by atomic layer deposition. The first moisture barrier layer is formed by atomic layer deposition. 提供一种使用氧化物半导体的顶部栅极结构的有机EL显示装置，有机EL显示装置在实现接触区域的低电阻化的同时，进一步提高了对水分的阻隔性。有机EL显示装置的TF