Patent attributes
An object is to increase the aperture ratio of a semiconductor device. The semiconductor device includes a driver circuit portion and a display portion (also referred to as a pixel portion) over the same substrate. The driver circuit portion includes a channel-etched thin film transistor for a driver circuit, in which a source electrode and a drain electrode are formed using a metal and a channel layer is formed using an oxide semiconductor, and a driver circuit wiring formed using a metal. The display portion includes a channel protection thin film transistor for a pixel, in which a source electrode and a drain electrode are formed using an oxide conductor and a semiconductor layer is formed using an oxide semiconductor, and a display portion wiring formed using an oxide conductor. The thin film transistors provided in the semiconductor device are formed with a resist mask formed using a multi-tone mask.
