B20‐type transition‐metal silicides or germanides are noncentrosymmetric materials hosting magnetic skyrmions, which are promising information carriers in spintronic devices. The prerequisite is to prepare thin films on technology‐relevant substrates with magnetic skyrmions stabilized at a broad temperature and magnetic‐field working window. A canonical example is the B20‐MnSi film grown on Si substrates. However, the as‐yet unavoidable contamination with MnSi1.7 occurs due to the lower nucleation temperature of this phase. In this work, a simple and efficient method to overcome this problem and prepare single‐phase MnSi films on Si substrates is reported. It is based on the millisecond reaction between metallic Mn and Si using flash‐lamp annealing (FLA). By controlling the FLA energy density, single‐phase MnSi or MnSi1.7 or their mixture can be grown at will. Compared with bulk MnSi, the prepared MnSi films show an increased Curie temperature of up to 41 K. In particular, the magnetic skyrmions are stable over a much wider temperature and magnetic‐field range than reported previously. The results constitute a novel phase selection approach for alloys and can help to enhance specific functional properties, such as the stability of magnetic skyrmions.

The nickel monogermanide (NiGe) phase is known for its electrical properties such as low ohmic and low contact resistance in group-IV-based electronics. In this work, thin films of nickel germanides (Ni–Ge) were formed by magnetron sputtering followed by flash lamp annealing (FLA). The formation of NiGe was investigated on three types of substrates: on amorphous (a-Ge) as well as polycrystalline Ge (poly-Ge) and on monocrystalline (100)-Ge (c-Ge) wafers. Substrate and NiGe structure characterization was performed by Raman, TEM, and XRD analyses. Hall Effect and four-point-probe measurements were used to characterize the films electrically. NiGe layers were successfully formed on different Ge substrates using 3-ms FLA. Electrical as well as XRD and TEM measurements are revealing the formation of Ni-rich hexagonal and cubic phases at lower temperatures accompanied by the formation of the low-resistivity orthorhombic NiGe phase. At higher annealing temperatures, Ni-rich phases are transforming into NiGe, as long as the supply of Ge is ensured. NiGe layer formation on a-Ge is accompanied by metal-induced crystallization and its elevated electrical resistivity compared with that of poly-Ge and c-Ge substrates. Specific resistivities for 30 nm Ni on Ge were determined to be 13.5 μΩ·cm for poly-Ge, 14.6 μΩ·cm for c-Ge, and 20.1 μΩ·cm for a-Ge.

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