Patent ID: 6963083

Claim:
A thin film transistor, comprising: a substrate; a crystallized semiconductor layer formed over the substrate having a channel region, low-density impurity regions and high-density impurity regions; a gate insulating layer formed on the crystallized semiconductor layer; a first gate electrode formed on the gate insulating layer having a width corresponding to the channel region; a second gate electrode formed on the first gate electrode and on the gate insulating layer such that the second gate electrode overlaps the low-density impurity regions, the second gate electrode having a first portion disposed on an uppermost surface of the first gate electrode and extending substantially parallel to the substrate and second portions having substantially uniform thickness disposed along opposing sidewalls of the first gate electrode and extending substantially perpendicular to the substrate; and a source electrode and a drain electrode respectively contacting the high-density impurity regions, wherein a thickness of the second portions of the second gate electrode are substantially equal to a width of the low-density impurity regions and terminal ends of the second portions of the second gate electrode directly contact the gate insulating layer and are substantially parallel to the substrate.