Field emission from electron-beam-irradiated bulk diamond

In order to extract electrons from bulk diamond, electron-beam (EB) irradia tion that controls the surface resistance of synthetic diamond was develope d. For slab-shaped bulk diamond which has various surface resistances, the characteristics of the emission current against the cathode voltage were fi tted to a Fowler-Nordheim (F-N) plot, which suggests that field emission ta kes place. Judging from the gradient of the F-N plot before and after EB ir radiation, this method produces a low-resistance and low-work function diam ond surface. The surface conductive layer formed by electron irradiation co ntributes electron emission from bulk diamond. Four spot patterns were obse rved after EB irradiation with a large emission angle of about 45 degrees. Using a bulk diamond stylus, work functions of 0.17 eV were measured from F -N plot gradients. In the case of the diamond stylus, some spots were obser ved within the emission angle of 17 degrees. (C) 1999 Elsevier Science B.V. All rights reserved.