Channel etching film transistor

The present invention provides a channel-etched thin film transistor, a channel-etched thin film transistor comprising: a source, the source comprising a main portion and a lead portion of the source; and a drain, a main portion which includes a drain and a drain wiring portion. A source wiring and a drain wiring portion portion having at least one side contact portion, the side contact portion in direct contact with sidewalls of the active layer. The average width of the side contact portions is narrower than the average width of the main portion of the source and the drain of the main portion corresponding one.