Manufacturing method of array substrate using dry etching processing and wet etching processing, array substrate and display device

A manufacturing method of an array substrate, an array substrate and a display device are disclosed. The manufacturing method of the array substrate includes: providing a base substrate (200); forming a semiconductor layer on the base substrate; depositing an etch stop layer material on the semiconductor layer; subjecting the etch stop layer material to a wet etching process to form an etch stop layer; subjecting the semiconductor layer to a dry etching process to form an active layer, wherein the active layer includes a first region and a second region surrounding the first region, an orthographic projection of the etch stop layer on the base substrate completely coincides with an orthographic projection of the first region of the active layer on the base substrate.