Carrier mobility enhanced diamond field effect transistor and preparation method thereof

The invention discloses a carrier mobility enhanced diamond field effect transistor and a preparation method thereof. The diamond field effect transistor is characterized in that a monocrystal diamond epitaxial film is arranged on a diamond substrate; the monocrystal diamond epitaxial film is provided with a first heavily-doped diamond film area and a second heavily-doped diamond film area; hydrogen terminal areas are arranged on the first heavily-doped diamond film area, the second heavily-doped diamond film area and the surface of the monocrystal diamond epitaxial film between the first heavily-doped diamond film area and the second heavily-doped diamond film area, and oxygen terminal areas are arranged on the surfaces of the other epitaxial films; the source electrode and the drain electrode are arranged on the channel region; a gate dielectric layer is arranged on the source electrode, the drain electrode and a channel region between the source electrode and the drain electrode; and a gate electrode is ar