Prediction of orientation relationships and interface structures between α-, β-, γ-FeSi2 and Si phases

A pure crystallogeometrical approach is proposed for predicting orientation relationships, habit planes and atomic structures of the interfaces between phases, which is applicable to systems of low-symmetry phases and epitaxial thin film growth. The suggested models are verified with the example of epitaxial growth of α-, γ- and β-FeSi2 silicide thin films on silicon substrates. The density of near-coincidence sites is shown to have a decisive role in the determination of epitaxial thin film orientation and explains the superior quality of β-FeSi2 thin grown on Si(111) over Si(001) substrates despite larger lattice misfits. Ideal conjunctions for interfaces between the silicide phases are predicted and this allows for utilization of a thin buffer α-FeSi2 layer for oriented growth of β-FeSi2 nanostructures on Si(001). The thermal expansion coefficients are obtained within quasi-harmonic approximation from the DFT calculations to study the influence of temperature on the lattice strains in the derived interfaces. Faster decrease of misfits at the α-FeSi2(001)||Si(001) interface compared to γ-FeSi2(001)||Si(001) elucidates the origins of temperature-driven change of the phase growing on silicon substrates. The proposed approach guides from bulk phase unit cells to the construction of the interface atomic structures and appears to be a powerful tool for the prediction of interfaces between arbitrary phases for subsequent theoretical investigation and epitaxial film synthesis.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:76

Enthalten in:

Acta crystallographica Section B, Structural science, crystal engineering and materials - 76(2020), Pt 3 vom: 01. Juni, Seite 469-482

Sprache:

Englisch

Beteiligte Personen:

Visotin, Maxim A [VerfasserIn]
Tarasov, I A [VerfasserIn]
Fedorov, A S [VerfasserIn]
Varnakov, S N [VerfasserIn]
Ovchinnikov, S G [VerfasserIn]

Links:

Volltext

Themen:

DFT calculations
Edge-to-edge matching
Interface structure
Iron silicide
Journal Article
Near-coincidence site
Orientation relationship
Structure prediction
Thermal expansion

Anmerkungen:

Date Revised 25.08.2020

published: Print-Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1107/S2052520620005727

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM314048715