Array substrate and manufacturing method thereof

A manufacturing method of an array substrate, comprising:

• providing a substrate;
• forming a patterned active layer on the substrate;
• forming an insulating layer on the active layer;
• forming a patterned common electrode layer and a patterned first metal layer on the insulating layer using a same photomask, wherein the patterned common electrode layer comprises touch electrodes;
• forming a patterned protective layer and a patterned pixel electrode layer on the first metal layer using a same photomask, wherein the patterned pixel electrode layer comprises pixel electrodes;
• and
• forming a patterned second metal layer on the pixel electrode layer, wherein the patterned second metal layer comprises drain electrodes and touch signal lines, the drain electrodes are electrically connected to the pixel electrodes, and the touch signal lines are electrically connected to the touch electrodes;
• wherein the step of forming the patterned common electrode layer and the patterned first metal layer on the insulating layer using the same photomask comprises:
• sequentially forming the common electrode layer, the first metal layer, and a first photoresist layer on the insulating layer;
• exposing the first photoresist layer by a first half-tone photomask, and then exposing the first photoresist layer to form a patterned first photoresist layer, wherein the patterned first photoresist layer comprises a first portion corresponding to a gate portion to be formed in the first metal layer, a second portion corresponding to a portion of the touch electrodes to be formed in the common electrode layer, and a first through hole corresponding to a source/drain area of the active layer;
• and a thickness of the first portion is greater than a thickness of the second portion;
• using the patterned first photoresist layer as a mask to etch the common electrode layer and the first metal layer by a wet etching process to form a gate electrode;
• performing heavy doping on the active layer through the first through hole;
• ashing the patterned first photoresist layer to thin the first portion and remove the second portion;
• removing exposed parts of the first metal layer by etching;
• removing remaining parts of the first photoresist layer;
• and
• performing light doping on the active layer.