Thin film transistor and manufacture method of thin film transistor

The invention provides a manufacture method of a thin film transistor. The manufacture method comprises the following steps that a source electrode and a drain electrode are provided, a pattern insulation layer is formed for locally covering the source electrode and the drain electrode, in addition, a part of source electrode and a part of drain electrode are exposed, an oxide semiconductor layer is formed and is in contact with the part of the source electrode and the part of the drain electrode, a grid electrode is provided, and a grid dielectric layer positioned between the oxide semiconductor layer and the grid electrode is provided. In addition, the thin film transistor is also provided.