Semi-adsorption-controlled growth window for half Heusler FeVSb epitaxial films

Abstract

The electronic, magnetic, thermoelectric, and topological properties of Heusler compounds (composition $XYZ$ or $X_{2}YZ$) are highly sensitive to stoichiometry and defects. Here we establish the existence and experimentally map the bounds of a \textit{semi} adsorption-controlled growth window for semiconducting half Heusler FeVSb films, grown by molecular beam epitaxy (MBE). We show that due to the high volatility of Sb, the Sb stoichiometry is self-limiting for a finite range of growth temperatures and Sb fluxes, similar to the growth of III-V semiconductors such as GaSb and GaAs. Films grown within this window are nearly structurally indistinguishable by X-ray diffraction (XRD) and reflection high energy electron diffraction (RHEED). The highest electron mobility and lowest background carrier density are obtained towards the Sb-rich bound of the window, suggesting that Sb-vacancies may be a common defect. Similar \textit{semi} adsorption-controlled bounds are expected for other ternary intermetallics that contain a volatile species $Z=$\{Sb, As, Bi\}, e.g., CoTiSb, LuPtSb, GdPtBi, and NiMnSb. However, outstanding challenges remain in controlling the remaining Fe/V ($X/Y$) transition metal stoichiometry.

References in corpus (7)

• Band gap and stability in the ternary intermetallic compounds NiSnM (M = Ti, Zr, Hf): A first principles study
• Observation of a topologically non-trivial surface state in half-Heusler PtLuSb (001) thin films
• Perspective: Heusler interfaces -- opportunities beyond spintronics?
• High electrical conductivity in the epitaxial polar metals LaAuGe and LaPtSb
• Surface reconstructions and transport of epitaxial PtLuSb (001) thin films grown by MBE
• Control of polymorphism during epitaxial growth of hyperferroelectric candidate LiZnSb on GaSb (111)B
• Electronically enhanced layer buckling and Au-Au dimerization in epitaxial LaAuSb films

Cited by in corpus (4)

• Electronic correlations in the semiconducting half-Heusler compound FeVSb
• Control of ternary alloy composition during remote epitaxy on graphene
• First-principles prediction of energy band gaps in 18-valence electron semiconducting half-Heusler compounds: Exploring the role of exchange and correlation
• Structure and magnetism in Fe-doped FeVSb and epitaxial Fe/FeVSb nanocomposite films