Thin film transistor with source and drain separately formed from amorphus silicon region

Abstract

A Thin Film Transistor comprises a gate electrode formed on a substrate; a gate insulation layer covering the gate electrode; an amorphous silicon (a-Si) region disposed on the gate insulation layer and above the gate electrode; a doped a-Si region formed on the a-Si region; the source and drain metal regions separately formed on the doped a-Si region and above the gate electrode, and isolated from the a-Si region; a passivation layer formed on the gate insulation layer and covering the source, drain and data-line (DL) metal regions; and a conductive layer formed on the passivation layer. The passivation layer has a first, second and third vias for respectively exposing the partial surfaces of the source, drain and DL metal regions. The first, second and third vias are filled with the conductive layer, so that the DL and source metal regions are connected via the conductive layer.