Observation of a non Fowler-Nordheim field-induced electron emission phenomenon from chemical vapor deposited diamond films

A field-induced electron emission phenomenon has been observed from nitroge n-doped diamond films deposited on molybdenum substrates by microwave plasm a enhanced chemical vapor deposition using N-2/CH4 as feedstock. Their fiel d-induced electron emission characteristics, i.e., current-voltage characte ristics and distribution of emission sites, were studied using the transpar ent anode imaging technique. A repeatable abrupt change of "on" and "off" s tates of emission was observed at two corresponding specific fields during circling of both increasing and decreasing applied gap fields. A plausible explanation is given to this type of field-induced electron emission phenom enon, in which a two-layer structure consisting of amorphous carbon and dia mond is proposed. (C) 1999 American Institute of Physics. [S0003-6951(99)02 535-8].