Thermal plasma synthesis of nanostructured silicon carbide films

Abstract

Two methods for the synthesis of nanostructured silicon carbide films are discussed and compared, thermal plasma chemical vapour deposition (TPCVD) and hypersonic plasma particle deposition (HPPD). Both methods produce β-SiC films with high growth rates on the order of 10 µm min −1. In TPCVD the generation of nanoscale grain sizes is caused by the fact that the film growth rate is much higher than the rate of surface diffusion. In HPPD a nanostructured film is grown by direct nanoparticle impact. In general, the films grown by TPCVD are denser and harder than in HPPD. X-ray diffraction spectra show that β-SiC is essentially the only crystalline phase in the TPCVD films, whereas in HPPD a silicon crystalline phase is also present, even for films that are overall carbon-rich. Evidence is presented to support the hypothesis that HPPD films actually grow by a combination of nanoparticle impact and CVD. If this parallel process can be controlled, it could potentially lead to the design and high-rate synthesis of new nanostructured materials.

Efficient sticking of surface-passivated Si nanospheres via phase-transition plasticity

“…Nanoparticle production in the gas phase, coupled with the application of chemical coatings and the deposition onto substrates, is a combination of aerosol technologies used for manufacturing novel nanostructured surfaces and thin films. [1][2][3][4][5][6] Chemical passivation in the gas phase is essential for preventing coalescence and large particle growth but makes the deposition step challenging. Deposition strategies have been developed, some necessitating the creation of defects in the substrate in order to pin the impinging nanoparticles, 1 which otherwise would be reflected.…”

Plasma-aided nanofabrication: where is the cutting edge?

“…We now turn our attention to contributions to this Cluster Issue [20][21][22][23][24][25][26] related to thermal plasmas.…”

“…We are pleased to introduce this Cluster Issue on plasmaaided fabrication of nanostructures and nanoassemblies, whose aim is to highlight the main features and competitive advantages of plasma-based nanofabrication approaches, methods and techniques. The Cluster Issue contains 20 contributions (including this review) representing different relevant areas [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. These areas are diverse and cover topics from 'simple' nanoparticles and nanostructured films to 'delicate' quantum dots, nanowires, nanoarrays and elements of nanodevices.…”

Preparation of silicon carbide SiC-based nanopowders by the aerosol-assisted synthesis and the DC thermal plasma synthesis methods

“…In those investigations, organosilanes or hydrocarbon/silane precursor systems were predominantly used for both the gas phase reactions [25][26][27][28][29][30][31][32][33][36][37][38] and solid state precursor conversions [34,35,43,45]. In the present study, two liquid-phase oxygen-bearing organosilicon precursors were tried to prepare SiC nanopowders of increased specific surface area that could be considered as affordable catalyst supports.…”

“…The resulting powders showed a bimodal distribution of particle sizes in the characteristic ranges depending on the carbon to silicon ratio. There have also been studies on using the thermal plasma for silicon carbide coatings, namely, plasma enhanced chemical vapor deposition PE CVD [25][26][27][28][29][30][31][32][33] or thermal plasma physical vapor deposition TP PDV [34,35]. These techniques were also used for making SiC nanoparticles [36][37][38][39][40][41][42][43][44].…”