| abstract |
A method of manufacturing a field effect transistor capable of patterning a source electrode and a drain electrode without using an etching stopper layer is provided. A gate electrode, source and drain electrodes, an active layer forming a channel between the source and drain electrodes, and a gate insulating layer provided between the gate electrode and the active layer. 13, a step of forming an active layer made of an oxide semiconductor, and a conductive film 150 to be a source and drain electrode, covering the active layer and forming a film. The step of patterning the conductive film by a step including wet etching and a step of forming source and drain electrodes, and the etching rate of the active layer is higher than the etching rate of the conductive film with respect to the etching solution of the conductive film used in the formation step And a treatment step for imparting resistance to the active layer against the etching solution. [Selection] Figure 3 |