Patent ID: 9117708
Filing Date: 2015-08-25
Classification: H01L

Abstract:
1. A thin film transistor comprising: a substrate; a gate electrode disposed on the substrate; a buffer layer partially covering an upper surface and completely covering inclined side surfaces of the gate electrode; a gate insulating layer disposed on the gate electrode and the buffer layer; an active layer disposed on the gate insulating layer; an etching stop layer disposed on the active layer, the etching stop layer comprising a first opening and a second opening; a source electrode disposed on the etching stop layer, the source electrode contacting with the active layer through the first opening; and a drain electrode disposed on the etching stop layer, the drain electrode contacting with the active layer through the second opening, wherein the gate insulating layer is disposed directly on the upper surface of the gate electrode, and the active layer is disposed directly on an upper surface of the gate insulating layer, and a thickness of the buffer layer at the upper surface of the gate electrode is smaller than a thickness of the buffer layer at the inclined side surfaces of the gate electrode, and the gate insulating layer is thinner than the buffer layer and wherein a distance between the gate electrode and the source electrode and a distance between the gate electrode and the drain electrode are increased by the buffer layer.