Novel Two-Step Method for Synthesis of High-Density Nanocrystalline Diamond Fibers

Abstract

We report a novel two-step method for the fabrication of high-density nanocrystalline diamond (NCD) fibers with lengths of 50-100 µm and diameters of 1-5 µm. This method includes the synthesis of templates (silica (a-SiO 2 ) nanofibers) by a conventional vapor-liquid-solid method and the conformal coating of the nanofibers with 15-20 nm sized NCD grains by a microwave plasma enhanced chemical vapor deposition technique in hydrogen-deficient conditions. A detailed microstructural analysis was performed to probe the interaction of the NCD grains with a-SiO 2 nanofibers. The specimen for transmission electron microscopy (TEM) was prepared using the focused ion beam lift-out method. Elemental line profiles across the core-sheath region of the fiber were probed by energy-dispersive X-ray microanalysis in scanning TEM mode. Room temperature micro-Raman (Ar + laser, 514 nm excitation wavelength, with a power of 25 mW) and parallel acquisition electron energy loss spectroscopy analysis were performed to study the crystalline quality of the NCD fiber. These novel materials may find applications in microand nanoelectromechanical systems and as heat sinks in microelectronics.

Diamond Nanowires: Fabrication, Structure, Properties, and Applications

“…This method includes the synthesis of templates (silica (a-SiO 2 ) nanofibers) by a conventional vapor-liquid-solid method and the conformal coating of the nanofibers with 15-20 nm sized nanocrystalline diamond (NCD) grains by microwave plasma enhanced chemical vapor deposition under hydrogen-deficient conditions. [93][94][95] The asprepared diamond nanowires showed good electron field emission properties. [94,95] Furthermore, our research group also reported a hot-filament chemical vapor deposition method using a Si nanowire template for the fabrication of arrays of boron-doped diamond nanowires and a 2D network of diamond nanowires.…”

Diamond Nanowires: Fabrication, Structure, Properties and Applications

“…The possibility of deposition of layered microdiamond coatings onto tungsten wires by the CVD method was demonstrated for the first time by May et al [62]. Afterward, many others reported successful the coating of microdiamond onto a variety of substrate wires including silicon carbide, copper, [66][67][68]. The as-prepared diamond nanowires showed good electron field emission properties [67,68].…”

Diamant‐Nanodrähte: Herstellung, Struktur, Eigenschaften und Anwendungen

“…[85][86][87][88] Gasphase-Flüssigkeit-Feststoff-Verfahren und konformes Überziehen der Nanofasern mit 15-20 nm großen nanokristallinen Diamantkçrnern (NCD) durch Mikrowellenplasma-verstärkte chemische Gasphasenabscheidung unter wasserstoffarmen Bedingungen. [93][94][95] Die erhaltenen Diamant-Nanodrähte zeigten gute Elektronen-Feldemissionseigenschaften. [94,95] Unsere Arbeitsgruppe beschrieb ein Verfahren der chemischen Heißfilament-Gasphasenabscheidung mit Si-Nanodrahttemplaten zum Herstellen Bordotierter Diamant-Nanodrahtfelder und 2D-Diamant-Nanodrahtnetzwerke.…”