Patent ID: 7763416

Claim:
A method of fabricating active device array substrate, comprising: providing a substrate and a multi-tone mask, wherein the multi-tone mask has at least four transparent areas; forming a gate electrode on the substrate; forming a gate insulation layer on the substrate to cover the gate electrode; forming a channel material layer on the gate insulation layer; forming a metal material layer on the channel material layer; forming a photoresist layer on the metal material layer and patterning the photoresist layer through the multi-tone mask so as to form a patterned photoresist layer, wherein the patterned photoresist layer has a recess and a protrusion with part of the metal material layer exposed outside the patterned photoresist layer, wherein the recess is above the gate electrode correspondingly and the protrusion is adjacent to the recess; removing the metal material layer and the channel material layer, uncovered by the patterned photoresist layer, to form a channel layer; performing a first removing process to remove the patterned photoresist layer at the recess so as to form an opening and expose part of the metal material layer; removing the metal material layer exposed to the opening to form a source and a drain and expose part of the channel layer; performing a second removing process to remove the patterned photoresist layer except the protrusion so that the protrusion can be on the drain; forming a protection layer on the substrate to cover the top of the protrusion, part of the gate insulating layer, the source, the drain, and part of the channel layer; performing a third removing process to remove the protrusion and the protection layer above the protrusion so that a contact window is formed in the protection layer with the exposure of part of the drain; and forming a pixel electrode on the substrate to fill the contact window so as to electrically connect with the drain.