Oxide thin film transistor, display device, and method for manufacturing array substrate

A method for manufacturing an oxide thin film transistor array substrate, comprising a step of forming an oxide thin film transistor on a base substrate, wherein the oxide thin film transistor comprises a gate electrode, a gate insulating layer, an oxide active layer pattern, a source electrode and a drain electrode, wherein the step of forming the oxide thin film transistor on the base substrate comprises:nforming the gate electrode on the base substrate;forming the gate insulating layer on the base substrate formed with the gate electrode;forming the source electrode and the drain electrode on the base substrate formed with the gate insulating layer; andforming the oxide active layer pattern on the base substrate formed with the source electrode and the drain electrode,wherein the step of forming the source electrode and the drain electrode on the base substrate formed with the gate insulating layer comprises:forming a first buffer layer, a source/drain metal layer and a second buffer layer in turn on the base substrate formed with the gate insulating layer;coating a photoresist on the second buffer layer;exposing and developing the photoresist, to form a photoresist-remained region and a photoresist-removed region, wherein the photoresist-remained region corresponds to a region where the source electrode and the drain electrode are located, and the photoresist-removed region corresponds to other regions;etching off the second buffer layer, the source/drain metal layer and the first buffer layer at the photoresist-removed region completely via an etching process; andpeeling off the remaining photoresist to form a pattern comprising the source electrode and the drain electrode.

A method for manufacturing an oxide thin film transistor array substrate, comprising a step of forming an oxide thin film transistor on a base substrate, wherein the oxide thin film transistor comprises a gate electrode, a gate insulating layer, an oxide active layer pattern, a source electrode and a drain electrode, wherein the step of forming the oxide thin film transistor on the base substrate comprises:nforming the gate electrode on the base substrate;forming the gate insulating layer on the base substrate formed with the gate electrode;forming the source electrode and the drain electrode on the base substrate formed with the gate insulating layer; andforming the oxide active layer pattern on the base substrate formed with the source electrode and the drain electrode,wherein the method further comprises a step of forming a common electrode on the base substrate while forming the gate electrode on the base substrate, which comprises:forming a transparent conductive layer and a gate metal layer in turn on the base substrate;coating a layer of photoresist on the gate metal layer;exposing and developing the photoresist via a half-tone or gray-tone mask plate to form a photoresist-removed region, a photoresist-totally-remained region and a photoresist-half-remained region; wherein the photoresist-totally-remained region corresponds to a region where the gate electrode is located, the photoresist-half-remained region corresponds to a region where the common electrode is located, and the photoresist-removed region corresponds to other regions;etching off the gate metal layer and the transparent conductive layer at the photoresist-removed region completely via a first etching process;removing the photoresist at the photoresist-half-remained region via an ashing process;etching off the gate metal layer at the photoresist-half-remained region completely via a second etching process, to form a pattern comprising the common electrode; andpeeling off the remaining photoresist, to form a pattern comprising the gate electrode.