Abstract: A high-efficiency flat type photo bar using a field emitter and a manufacturing method thereof, including: a substrate; a cathode part which is formed as an electrode on an upper portion of the substrate; a nano-field emitter which is patterned at a constant interval on the cathode part; a gate part which is formed horizontally to the cathode part so as to induce the emission of electrons from the field emitter; and an anode part which is insulated and separated from an upper portion of the gate part so as to be formed horizontally to the upper portion of the gate part and comprises a target material.