Thin film transistor and manufacturing method thereof, array substrate, and display apparatus

The present invention provides a thin film transistor and a manufacturing method thereof, an array substrate, and a display apparatus. The thin film transistor of the present invention comprises a gate, a gate insulation layer, a semiconductor active region, and a source and a drain connected with the semiconductor active region, and further comprises a surface charge transfer layer in contact with the semiconductor active region, the surface charge transfer layer is located above or below the semiconductor active region, and is used for causing the semiconductor active region to generate a large number of holes or electrons therein without changing the lattice structure of the semiconductor active region. In the thin film transistor, charge transfer occurs between the semiconductor active region and the surface charge transfer layer so that the doped semiconductor active region is formed, thus the performance of the thin film transistor is significantly improved.