Thin film transistor display and method of fabrication

Abstract

A thin film transistor (TFT) display and a method of fabricating the same are disclosed. The display is formed on a substrate, and the substrate includes a transistor area for forming a transistor, and a pad area for forming a pad. The first step of the method is to form a gate electrode and a pad electrode on the transistor area and the pad area, respectively. Then, an insulating layer is deposited on the substrate and has a pad opening to expose the pad electrode. Next, a semiconductor layer, a doped silicon conductive layer, and a second metal layer are deposited, respectively, above the insulating layer. Then, a channel area is defined in the transistor area by removing portions of the second metal layer and the doped silicon layer within the channel area and outside the transistor area. The remaining second metal layer in the transistor area forms a source metal layer and a drain metal layer. A patterned passivation layer is formed to expose the semiconductor layer outside the transistor area. Finally, the first insulating layer is exposed outside the transistor area and the pad electrode is exposed within the pad opening after etching away the unprotected portions of the semiconductor layer and the insulating layer.