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 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 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.

中文翻译：

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半霍斯勒FeVSb外延膜的半吸附控制生长窗口

Heusler化合物的电子，磁，热电和拓扑性质（组成 $Xÿž$ 要么 $X_2ÿž$）对化学计量和缺陷高度敏感。在这里，我们建立了存在性并通过实验绘制了通过分子束外延（MBE）生长的半导体半Heusler FeVSb薄膜的半吸附控制生长窗口的边界。我们表明，由于Sb的高挥发性，Sb的化学计量在一定范围内的生长温度和Sb通量上是自限性的，类似于III-V半导体（如GaSb和GaAs）的生长。在该窗口内生长的薄膜在结构上几乎无法通过X射线衍射（XRD）和反射高能电子衍射（RHEED）来区分。朝着窗口的富Sb边界获得了最高的电子迁移率和最低的背景载流子密度，这表明Sb空位可能是常见的缺陷。相似的半含有挥发性物质的其他三元金属间化合物预期具有吸附控制的界限 $ž=${Sb，As，Bi}，例如CoTiSb，LuPtSb，GdPtBi和NiMnSb。然而，在控制剩余的Fe / V方面仍存在严峻的挑战（$X/ÿ$）过渡金属化学计量。