This study explores the field emission properties of nitrogen-doped diamond grown by microwave plasma chemical vapor deposition. Over 70 nitrogen-doped diamond samples were grown on silicon and molybdenum under varying process conditions. Under certain conditions, films can be grown which exhibit photoluminescence bands at 1.945 and 2.154 eV that are attributed to single substitutional nitrogen. Photoelectron emission microscopy with UV free electron laser excitation indicated a 0 or negative electron affinity. Field emission characteristics were measured in an ultrahigh vacuum with a variable distance anode technique. For samples grown with gas phase [N]/[C] ratios less than 10, damage from microarcs occurred during the field emission measurements. Samples grown at higher [N]/[C] content could be measured prior to an arcing event. Contrary to other reports on nitrogen-doped diamond, these measurements indicate relatively high threshold fields (>100 V/μm) for electron emission. We suggest that the nitrogen in these films is compensated by defects. A defect-enhanced electron emission model from these films is discussed.

Controlled slow-speed microcutting tests were made on single crystal silicon. Micro-Raman spectroscopy confirmed the presence of amorphous silicon within the microcutting grooves as well as in the debris particles removed from the grooves. These results indicate that pressure-induced transformation to metallic silicon can occur during microcutting and the ductile metallic phase will facilitate the cutting process. Raman spectroscopy further indicated the presence of large residual tensile strains in some areas of the microcutting grooves.

Articles you may be interested inComposite-layered solid-state field controlled emitter for a better control of the cathode surface barrier J. Vac. Sci. Technol. B 23, 824 (2005); 10.1116/1.1864065Field emission characteristics of boron nitride films deposited on Si substrates with cubic boron nitride crystal grains J.Cold cathode structures have been fabricated using AlN and graded AlGaN structures ͑deposited on n-type 6H-SiC͒ as the thin film emitting layer. The cathodes consist of an aluminum grid layer separated from the nitride layer by a SiO 2 layer and etched to form arrays of either 1, 3, or 5 m holes through which the emitting nitride surface is exposed. After fabrication, a hydrogen plasma exposure was employed to activate the cathodes. Cathode devices with 5 m holes displayed emission for up to 30 min before failing. Maximum emission currents ranged from 10-100 nA and required grid voltages ranging from 20-110 V. The grid currents were typically 1 to 10 4 times the collector currents.

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