ELECTRON FIELD-EMISSION FROM CHEMICAL-VAPOR-DEPOSITED DIAMOND

Diamond films and islands have been synthesized with varying defect de nsities and dopant levels by chemical vapor deposition for field emiss ion display applications. Vacuum field emission measurements show that the electric held required to induce electron emission from diamond c an be significantly reduced when the samples are properly grown or pos tgrowth processed so that they contain a substantial amount of structu ral defects. The defective diamond is characterized by a broadened pea k at 1332 cm(-1) in Raman spectroscopy with a full width at half-maxim um in the range of 7-11 cm(-1). These materials require a turn-on fiel d (for a current density of 0.01 mA/cm(2)) as low as 15 V/mu m, and a threshold held (for a current density of 10 mA/cm(2)) as low as 30 V/m u m for electron emission. These field values are almost an order of m agnitude lower than those required for high quality, p-type semiconduc ting diamond. Detailed numerical analysis of the emission current-volt age data from multiple diamond tips with varying geometric and electro nic properties is presented, and the mechanisms responsible for such l ow voltage electron emission from defective diamond are discussed. (C) 1996 American Vacuum Society.