Electron field emission from ion-implanted diamond

Abstract

Diamond films and islands grown by chemical vapor deposition were implanted with boron, sodium, and carbon ions at doses of 10 14-10 15 /cm 2. This structural modification at the subsurface resulted in a significant reduction of the electric field required for electron emission. The threshold field for producing a current density of 10 mA/cm 2 can be as low as 42 V/m for the as-implanted diamond compared to 164 V/m for the high quality p-type diamond. When the ion-implanted samples were annealed at high temperatures in order to anneal out the implantation-induced defects, the low-field electron emission capability of diamond disappeared. These results further confirm our earlier findings about the role of defects in the electron emission from undoped or p-type doped diamond and indicate that the improved emission characteristics of as-implanted diamond is due to the defects created by the ion implantation process.

The potential application of ultra-nanocrystalline diamond films for heavy ion irradiation detection

“…Many reports have discussed the effects of ion beam irradiation on the characteristics of diamond and related materials, such as type IIa diamond, 15 diamond-like carbon films, 16 taC, 17 graphite 18 and polycrystalline CVD diamond films. [19][20][21] Especially, Pandey et al 22 and Koinkar et al 23 have studied the field emission enhancement by swift heavy ion irradiation in CVD diamonds.…”

Field Emission from As-Grown and Ion-Beam-Sharpened Diamond Particles Deposited on Silicon Tips

“…As it is seen, the voltage corresponding to the onset of the emission, at measurable (in our experiments) 10" A, decreased strongly (from about 1300 V down to about 150 V) when the emitter was sharpened. This decrease we connect with at least two factors: (a) decrease of the curvature radius of the emitter fkom about 0.5 mm to about 20 nm; (b) tentative formation of defects in the emitter during the ion-beam bombardment with corresponding improvement of the field emission, as it was supposed by Zhu et a1 [13].…”

Electron field emission from surface treated tetrahedral amorphous carbon films

“…2 It also means that these films can be produced with a whole gamut of different properties resulting in the difficulties to propose a single model to explain the emission mechanism. A number of models have been proposed based on the negative electron affinity, 3 defect bands in diamond, 4 space charge induced band bending, 5 surface dipole controlled emission, 6 and field enhancement due to surface features. 7 Although they can be used to fit some emission data from different types of films, none of them is universally acceptable.…”