THIN FILM TRANSISTOR AND DISPLAY DEVICE

摘要

PROBLEM TO BE SOLVED: To reduce an off-state current of a bottom gate type thin film transistor in which a semiconductor layer is shielded by a gate electrode. SOLUTION: A thin film transistor includes: a gate electrode layer; a first semiconductor layer; a second semiconductor layer having lower carrier mobility than the first semiconductor layer, which is provided over and in contact with the first semiconductor layer; a gate insulating layer which is provided between and in contact with the gate electrode layer and the first semiconductor layer; first impurity semiconductor layers which are provided so as to be in contact with the second semiconductor layer; second impurity semiconductor layers which are provided so as to be partially in contact with the first impurity semiconductor layers and the first and second semiconductor layers; and source and drain electrode layers which are provided so as to be in contact with entire surfaces of the second impurity semiconductor layers. An entire surface of the first semiconductor layer on a gate electrode layer side overlaps with the gate electrode layer. COPYRIGHT: (C)2010,JPO&INPIT