ELECTRON FIELD-EMISSION FROM ION-IMPLANTED DIAMOND

Diamond films and islands grown by chemical vapor deposition were impl anted with boron, sodium, and carbon ions at doses of 10(14)-10(15)/cm (2). This structural modification at the subsurface resulted in a sign ificant reduction of the electric field required for electron emission . The threshold field for producing a current density of 10 mA/cm(2) c an be as low as 42 V/mu m for the as-implanted diamond compared to 164 V/mu m for the high quality p-type diamond. When the ion-implanted sa mples were annealed at high temperatures in order to anneal out the im plantation-induced defects, the low-field electron emission capability of diamond disappeared. These results further confirm our earlier fin dings about the role of defects in the electron emission from undoped or p-type doped diamond and indicate that the improved emission charac teristics of as-implanted diamond is due to the defects created by the ion implantation process. (C) 1995 American Institute of Physics.