The invention relates to a semiconductor film transistor and a manufacture method thereof and a display device having the semiconductor film transistor and a backboard thereof. The semiconductor film transistor comprises a first substrate, a first grid, a first source electrode, a first drain electrode, a first grid insulation layer, a first wire, a first electrode and a first semiconductor. The first grid insulation layer covers the first grid and is connected with the first substrate; the first source electrode and the first drain electrode are arranged on the first grid insulation layer; the first semiconductor covers the first source electrode and the first drain electrode and is in interval arrangement with the first wire and the first electrode; and the first wire and the first electrode are connected with the first semiconductor through a first conductive material. Since the source electrode and the drain electrode are covered by the semiconductor, when patterning etching is carried out on the semiconductor, the source electrode and the drain electrode do not be oxidized by etching oxygen ions due to the separation of the semiconductor, and the wires and electrodes are not easy to be oxidized; and the semiconductor film transistor has better element characteristic.