Study of instability in the field electron emission from amorphous diamondfilms

Details are given of an experimental study of the current-voltage character istics and instability of the field electron emission from amorphous diamon d films prepared using a magnetic field-filtered ion deposition technique. A switch-on phenomenon is observed, and two types of instability are found, i.e., fluctuation at low currents and an abrupt change in emission associa ted with local breakdown events at high currents. Finally, it is found that , in order to establish stable emission with a current density approaching 50 mA/cm(2), it is necessary to undergo the switch-on and local breakdown p rocesses. These phenomena are characterized,: and the physical mechanisms r esponsible for them are proposed. (C) 1999 American Vacuum Society. [S0734- 211X(99)05402-5].