The invention provides an
oxide thin film transistor, a manufacturing method of the
oxide thin film transistor, an array substrate and a
display device, and relates to the technical field of
liquid crystal display. The manufacturing method of the
oxide thin film transistor includes the steps that a grid
electrode, a grid insulating layer and an
oxide semiconductor thin film are sequentially formed in a substrate; first
photoresist is formed in an
active layer area of the
oxide semiconductor thin film, and a channel area is thicker than a non-channel area; the first
photoresist of the channel area is reserved; a source drain
metal thin film is formed on
active layer patterns, second
photoresist on the source drain
metal thin film is reserved, and the edge of the first photoresist of the channel area is covered with the source drain
metal thin film; source
electrode patterns and drain
electrode patterns are obtained. According to the
oxide thin film transistor, the manufacturing method of the
oxide thin film transistor, the array substrate and the
display device, when the initial source electrode patterns and the initial drain electrode patterns are formed, the photoresist is utilized to replace a protective layer to protect an
active layer, the final source electrode patterns and the final drain electrode patterns are formed through a photoresist stripping technology, and therefore the length of a channel of the
oxide thin film transistor is shortened.