HIGHLY EFFICIENT ELECTRON-EMISSION DIODE OF SINGLE-CRYSTALLINE CHEMICAL-VAPOR-DEPOSITION DIAMOND

A novel type of flat electron emission diode with a high emission effi ciency has been fabricated using single crystalline diamond thin films homoepitaxially grown on thick high-pressure-synthesized diamond. For the formation of the buried electrode, 180-keV N+ ions were implanted into the homoepitaxial layer grown by microwave plasma chemical-vapor -deposition (CVD) method to a dose 1 x 10(16) ions/cm(2) at room tempe rature. Since this process created a significant damage in the specime n surface layer working as the electron emission surface, a high quali ty diamond layer was subsequently overgrown to recover the damaged sur face. Applying voltages of sub-kV between the hydrogenated surface and the buried electrode results in an efficient electron emission (>10%) .