Thin film transistor and active matrix organic light emitting diode assembly

摘要

A thin film transistor includes a semiconductor layer including a source region, a drain region, a channel region, first lightly doped drain regions adjacent to the channel region and second lightly doped drain regions adjacent to the first lightly doped drain regions; wherein the second lightly doped drain regions have a doping concentration lower than that of the first lightly doped drain regions. According to the present application, the leakage current in a switching transistor may be further reduced, thereby avoiding instability and even failure in the operation of the assembly caused by overlarge leakage current.

主权项

1. A thin film transistor , comprising:
a semiconductor layer having a source region, a drain region, a channel region, first lightly doped drain regions adjacent to the channel region and second lightly drain regions adjacent to the first lightly doped drain regions; wherein one of the second lightly doped drain regions is adjacent to the source region, and the other of the second lightly doped drain regions is adjacent to the drain region; and the second lightly doped drain regions have a doping concentration lower than that of the first lightly doped drain regions; the thin film transistor further comprises: a substrate: a buffer layer on the substrate, the semiconductor layer being on the buffer layer; a first gate insulating layer covering the semiconductor layer; a second gate insulating layer foot on the first gate insulating layer, the second gate insulating layer foot having a width smaller that that of the first gate insulating layer, and a gate electrode on the second gate insulating later foot: wherein an edge of the second gate insulating layer foot has a protrusion, such that a thickness of the edge is larger that that of other part of the second gate insulating layer foot.