Editors : P. Holloway, J. Itoh, K.L. Jensen, W. Mackie, R. Nemanich, D. Temple, T. Trottier
a1 Material Science dept, Cambridge University, Cambridge., U.K.
a2 Electronic Materials & Devices, Dept of Engineering, Cambridge University, Cambridge. CB2 1PZ., U.K.
Very low threshold field emission from undoped microcrystalline diamond films grown by the hot filament chemical vapour deposition process (HFCVD) is reported. The effect of crystal size, methane concentration and the temperature has been studied. The microcrystalline diamond films grown using 3% methane (CH4) / hydrogen (H2) gas mixture ratio under varying deposition temperatures exhibit very low emission threshold fields. The threshold fields varied from 0.4 V/ [.proportional]m to 1 V/[.proportional]m for an emission current density of 1 [.proportional]A/cm2. A correlation between the emission characteristics and the material properties is presented. These films exhibit an emission site density of ∼ 104−105/cm2 at an applied field of 3 V/[.proportional]m.
p1 Present address : Sistec & Dept of Electronic &Photonic Systems Engineering, Kochi University of Technology, 185, Miyanokuchi, Tosayamada, Kochi 782-8502, Japan.
p2 Present address : Dr. XiLin Peng, Research Associate, Physics Department, 1150 University Ave. University of Wisconsin-Madison, Wisconsin, WI53706, USA