Preparation method of array substrate, array substrate and display device

The invention provides a preparation method of an array substrate, the array substrate and a display device, and belongs to the technical field of display. The preparation method of the array substrate comprises the following steps: forming a first conductive layer on a substrate; forming a second conductive layer on one side, deviating from the substrate, of the first conductive layer; coating a photoresist layer on the second conductive layer, and exposing and developing the photoresist layer to obtain a first reserved part of photoresist; forming a first conductive pattern through a composition process, and etching the first conductive layer by taking the first conductive pattern as a mask to obtain a second conductive pattern; ashing the first reserved part of the photoresist to obtain a second reserved part of the photoresist; and etching the first conductive pattern by taking the second reserved part of the photoresist as a mask to obtain a third conductive pattern. 本公开提供一种阵列基板的制备方法、阵列基板和显示装置，属于显示技术领域。本