Nitrogen-Incorporated Boron-Doped Nanocrystalline Diamond Nanowires for Microplasma Illumination

Abstract

The origin of nitrogen-incorporated boron-doped nanocrystalline diamond (NB-NCD) nanowires as a function of substrate temperature (T s ) in H 2 /CH 4 /B 2 H 6 /N 2 reactant gases is systematically addressed. Because of T s , there is a drastic modification in the dimensional structure and microstructure and hence in the several properties of the NB-NCD films. The NB-NCD films grown at low T s (400 °C) contain faceted diamond grains. The morphology changes to nanosized diamond grains for NB-NCD films grown at 550 °C (or 700 °C). Interestingly, the NB-NCD films grown at 850 °C possess one-dimensional nanowirelike morphological grains. These nanowire-like NB-NCD films possess the co-existence of the sp 3 -diamond phase and the sp 2graphitic phase, where diamond nanowires are surrounded by sp 2 -graphitic phases at grain boundaries. The optical emission spectroscopy studies stated that the CN, BH, and C 2 species in the plasma are the main factors for the origin of nanowire-like conducting diamond grains and the materialization of graphitic phases at the grain boundaries. Moreover, conductive atomic force microscopy studies reveal that the NB-NCD films grown at 850 °C show a large number of emission sites from the grains and the grain boundaries. While boron doping improved the electrical conductivity of the NCD grains, the nitrogen incorporation eased the generation of graphitic phases at the grain boundaries that afford conducting channels for the electrons, thus achieving a high electrical conductivity for the NB-NCD films grown at 850 °C. The microplasma devices using these nanowire-like NB-NCD films as cathodes display superior plasma illumination properties with a threshold field of 3300 V/μm and plasma current density of 1.04 mA/cm 2 with a supplied voltage of 520 V and a lifetime stability of 520 min. The outstanding plasma illumination characteristics of these conducting nanowire-like NB-NCD films make them appropriate as cathodes and pave the way for the utilization of these materials in various microplasma device applications.

A Ti‐Doped Chemical Vapor Deposition Diamond Device as Artificial Synapse for Neuromorphic Applications

“…Such a topographic configuration is reasonably due to the presence of the nitrogen flux, that introduces the doping species in the reactor during the synthesis. [25] In fact, the addition of an inert gas during the chemical vapor deposition (CVD) growth increases the number of diamond nuclei density, [26,27] promoting the secondary nucleation and inducing a ball-like morphology. An in-depth AFM analysis provided a surface root mean square roughness value (Sq) of about 180 nm, in line with the roundish shape and the homogenous distribution of the diamond grains.…”

Nanoscale Investigation on the Improvement of Electrical Properties of Boron-Doped Diamond Nanostructures for High-Performance Plasma Displays

“…low V bk of 360 V, high J PI of 8.0 mA/cm 2 with high lifetime stability, which is comparable with the other cathode materials reported earlier (Table ). ,,,,− All of the aforementioned investigations show that nanostructuring in BDD films improves the electrical properties, resulting in enhanced PI characteristics, making diamond nanostructures a promising cathode material for PD.…”

Microplasma Illumination Enhancement in N+P‐Co‐Ion‐Implanted Nanocrystalline Diamond Films

“…Growth of NCD Films: The (100) silicon substrates (size 1 Â 1 cm) were nucleated by spin-coating with 5 nm sized detonation nanodiamond particles, which are dispersed in deionized water. [8,10] ASTeX 6500 series microwave plasma-enhanced CVD system was used to grow NCD films on silicon substrates for a growth time of 1 h using CH 4 (6%), H 2 (89%), and N 2 (5%) gas mixture of total flux 500 sccm. The microwave power and working pressure were set at 3000 W and 30 Torr, respectively, attaining a growth temperature of 650 °C (estimated using a single-color optical pyrometer).…”

“…Electrically conducting diamond films were synthesized using appropriate dopants and impurities. [8,9] The induction of nanographitic phases in the grain boundaries of diamond films by incorporation of nitrogen increases the proportion of conduction paths, resulting in the enhancement of the electrical conductivity of the films. [10] However, the insulating nature of diamond grains confines the electrical conduction to the grain boundaries of diamond films, thus restraining the usage of nitrogenincorporated diamond films in device applications.…”