Titel
Ni-mediated reactions in nanocrystalline diamond on Si substrates: the role of the oxide barrier
Autor*in
Oleksandr Romanyuk
Institute of Physics, Czech Academy of Sciences
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Abstract
Nanocrystalline diamond (NCD) films grown on Si substrates by microwave plasma enhanced chemical vapor deposition (MWPECVD) were subjected to Ni-mediated graphitization to cover them with a conductive layer. Results of transmission electron microscopy including electron energy-loss spectroscopy of cross-sectional samples demonstrate that the oxide layer on Si substrates (∼5 nm native SiO2) has been damaged by microwave plasma during the early stage of NCD growth. During the heat treatment for graphitizing the NCD layer, the permeability or absence of the oxide barrier allow Ni nanoparticles to diffuse into the Si substrate and cause additional solid-state reactions producing pyramidal crystals of NiSi2 and SiC nanocrystals. The latter are found impinged into the NiSi2 pyramids but only when the interfacial oxide layer is absent, replaced by amorphous SiC. The complex phase morphology of the samples is also reflected in the temperature dependence of electrical conductivity, where multiple pathways of the electronic transport dominate in different temperature regions. We present models explaining the observed cascade of solid-state reactions and resulting electronic transport properties of such heterostructures.
Stichwort
General ChemistryGeneral Chemical Engineering
Objekt-Typ
Sprache
Englisch [eng]
Persistent identifier
Erschienen in
Titel
RSC Advances
Band
10
Ausgabe
14
ISSN
2046-2069
Erscheinungsdatum
2020
Seitenanfang
8224
Seitenende
8232
Publication
Royal Society of Chemistry (RSC)
Projekt
Kod / Identifikator
I 2344-N36
Fördergeber
Erscheinungsdatum
2020
Zugänglichkeit
Rechte
Rechteangabe
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