Microplasma device architectures with various diamond nanostructures

Abstract

Diamond nanostructures (DNSs) were synthesized from three different morphological diamond, including microcrystalline diamond (MCD), nanocrystalline diamond (NCD), and ultrananocrystalline diamond (UNCD) films by RIE method and the plasma behavior of microplasma devices using the DNSs and diamond films as cathode materials were investigated. The Paschencurve approach revealed that the -value of diamond materials is similar irrespective of the microstructure (MCD, NCD and UNCD) and geometry (DNSs and diamond films) of the materials. The diamond materials show markedly larger -coefficient than the conventional metallic cathode materials such as Mo and resulted in markedly better plasma illumination behavior for the corresponding microplasma devices. Moreover, the plasma illumination behavior, i.e., the voltage dependence of plasma current density (J pl-V) and plasma density (n e-V) characteristics and the robustness of the devices varied markedly with the microstructure and geometry of the cathode materials that is closely correlated with the EFE properties of the cathode materials. The UNCD nano-pillars, which possess the best EFE properties, resulted in markedly superior plasma behavior, whereas the MCD diamond films, which possess the worst EFE properties, led to inferior plasma behavior than the other kind of diamond cathode materials. Therefore, the detailed study Page 1 of 29 AUTHOR SUBMITTED MANUSCRIPT-MRX-102981 demonstrates that enhancement of plasma characteristics is due to collective effect of EFE behavior and secondary electron emission properties of cathode materials.

Diamond Nanostructures at Different Dimensions: Synthesis and Applications

“…It is normally prepared through the RIE of a thick diamond film. Up to now, diamond nanocones have been successfully applied in the fields of clinical sterilization [ 54 ] as well as the construction of plasma illumination devices, [ 55 ] field emission, [ 56 ] and electrochemical sensors. [ 57 ] In some diamond nanopillars, only half of them were collected for photons that were guided to two directions parallel to two symmetric axes of pillars.…”

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

“…Chemical vapor deposition (CVD) grown diamond film exhibits high thermal conductivity, good rigidity, high chemical inertness, low sputtering yield, and particularly, large γ coefficient, rendering it a suitable cathode material for MI devices. [ 6,7 ] The huge assurance that the diamond endures as an efficient cathode in the MI devices necessitates the films to be conductive. Electrically conducting diamond films were synthesized using appropriate dopants and impurities.…”

“…An important factor for the choice of cathode materials for MI devices is that the material should be efficient in generating abundant secondary electrons (i.e., large secondary electron emission [γ] coefficient), thereby increasing the stability of micro-discharges.Chemical vapor deposition (CVD) grown diamond film exhibits high thermal conductivity, good rigidity, high chemical inertness, low sputtering yield, and particularly, large γ coefficient, rendering it a suitable cathode material for MI devices. [6,7] The huge assurance that the diamond endures as an efficient cathode in the MI devices necessitates the films to be conductive. Electrically conducting diamond films were synthesized using appropriate dopants and impurities.…”

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

“…9 Due to high chemical inertness, high thermal conductivity, low sputtering yield, rigidity, insensitivity to numerous processing conditions, wide band gap, and negative electron affinity characteristics, diamond thin films synthesized using chemical vapor deposition (CVD) systems usually exhibit a large secondary electron emission coefficient 10 and those are highly suitable as cathodes for microplasma devices. 11 Along with the abovementioned properties, diamond films should be electrically conducting to be an efficient cathode in microplasma devices. Using suitable dopants and impurities, it is practicable to synthesize electrically conducting diamond films and also the conductivity can be tailored related to the application requirement.…”