Patent ID: 9099440
Filing Date: 2015-08-04
Classification: H01L

Abstract:
1. A manufacturing method of an array substrate, comprising: forming an underlying metal thin film on a substrate, and forming at least a gate electrode of a TFT by a mask process; forming a gate insulating layer overlying the gate electrode; forming a metal oxide semiconductor thin film and a top metal thin film, and performing a mask process to the metal oxide semiconductor thin film and the top metal thin film, to form a source electrode and a drain electrode of the TFT and an active layer opposing the gate electrode respectively; and forming a passivation layer overlying the source electrode and the drain electrode, and forming a contact hole at the position of the drain electrode which connects a pixel electrode, wherein during the mask process to the top metal thin film, a hydrogen peroxide-based etchant with pH value between 6-8 is used to etch the top metal thin film, wherein the step of forming a source electrode and a drain electrode of the TFT and an active layer opposing the gate electrode comprises: forming the metal oxide semiconductor thin film and the top metal thin film sequentially; applying photoresist to the sequentially formed two thin films, the photoresist being divided into a partially remained region, a completely remained region and a completely removed region, and according to the above divided regions, by a single exposure and development, removing photoresist in the completely removed region and having photoresist in the completely remained region remain thicker than that in the partially remained region; etching the top metal thin film in the completely removed region with the hydrogen peroxide-based etchant; etching the metal oxide film in the completely removed region with acid etchant that does not react with the top metal, so as to form an active layer; ashing photoresist that is left, in order to remove photoresist in the partially remained region and have part of photoresist in the completely remained region remain; and etching the top metal thin film in the partially remained region with the hydrogen peroxide-based etchant, so as to form a source electrode and a drain electrode.