Field emission from tetrahedral amorphous carbon

Field emission has been measured from a series of tetrahedrally bonded amorphous carbon (ta-C) films produced by the filtered cathodic vacuum arc. The threshold field and current densities achievable have been studied as a function of their sp(3) content and of nitrogen incorporation. Typical undoped ta-C films are found to have a threshold field of 10-20 V/mu m, decreasing with increasing sp(3) content, and optimally nitrogen doped films exhibit threshold fields as low as 3-5 V/mu m. (C) 1997 American Institute of Physics.