The invention belongs to the technical field of display and discloses a
thin film transistor, a preparation method thereof, an array substrate, a display panel and a
display device. The
thin film transistor comprises a substrate, as well as an
active layer and a source-drain
electrode which are sequentially stacked on the substrate; and the projection of a source
electrode in the source-drain
electrode on the substrate is overlapped with the projection of part of the edge of the
active layer on the substrate. According to the
thin film transistor, the illumination-receiving area of the activelayer is small, so that the generation of holes can be effectively reduced, the concentration of
photon-generated carriers under an illumination condition is reduced, and therefore, the defect statessuch as hole capture probability increase and
threshold voltage reduction, of the TFT working in a high-temperature illumination environment are avoided, and the performance of the TFT device in the high-temperature illumination environment is improved. When the thin film
transistor is applied to the display panel, the working performance of the display product in a high-temperature environment can be improved, and the reliability of the display product is enhanced.