Thin film transistor and method for manufacturing the same, array substrate, and display device

The present invention discloses a thin film transistor and a method for manufacturing the same, an array substrate and a display device. The performance of the thin film transistor can be improved and thereby the image quality can be improved by an increase in the width of the conducting area of a thin film transistor without change of the capacitance of the source electrode. The thin film transistor comprises a substrate, a gate electrode, a source electrode, at least two drain electrodes, a semiconductor layer, a gate electrode protection layer located between the gate electrode and the semiconductor layer and an etch stopping layer located between the semiconductor layer and the source electrode with the drain electrode, wherein the source electrode and the drain electrodes are respectively connected with the semiconductor layer by a via hole.