Fabrication of electron emitter device using polycrystalline diamond film

An electron emitter device using a polycrystalline diamond film has been de veloped. The device is composed of a cathode of a polycrystalline diamond f ilm, gate electrodes of aluminum, and an insulating layer of a diamond-like carbon film. The diamond film was deposited on an n-type Si wafer by the c onventional microwave plasma chemical vapor deposition (CVD) method, the di amond-like carbon film was deposited by an electron cyclotron resonance (EC R) plasma CVD method, and the aluminum electrodes were deposited by an elec tron beam evaporator and patterned by photolithography. The diamondlike car bon layer on the cathode was removed by oxygen plasma etching. Electron emi ssion from the cathode to the gate electrodes was observed at a gate voltag e of more than 30 V and the emission current was 0.5 mA at 40 V.