Atomic force micrograph of the sample surface after the growth was finished, revealing an MnAs island pattern on the GaAs surface.
Schematic view of the epitaxial relationship of MnAs on GaAs(001). The and orientations of the MnAs film are shown.
X-ray grazing incidence diffraction curve ( scan, circles) measured at a substrate temperature of along the GaAs direction with the GaAs substrate and the MnAs 00.2 and 00.4 layer reflections (from the domains in orientation). The MnAs 11.0 reflection from the domains in orientation is also visible. The MnAs 00.2 and 00.4 peaks are fitted to the Gaussian functions (solid lines).
X-ray grazing incidence diffraction curves ( scans, circles) measured at a substrate temperature of along GaAs  with the GaAs 220 and 440 substrates and the MnAs 11.0 and 22.0 layer reflections of the domains in orientation. The MnAs 11.0 and 22.0 peaks are fitted to the Gaussian functions (solid lines).
X-ray grazing incidence diffraction curves ( scans) measured at a substrate temperature of along GaAs  with the GaAs 220 substrate and the MnAs 11.0 layer reflections during the growth of the MnAs film. The approximate layer thicknesses (island heights) determined from a comparison of the corresponding growth times with the overall growth time and the final layer thickness are indicated. A distinct MnAs 11.0 peak is observed already at an average thickness of monolayer (ML). Both the position and the half width of the MnAs 11.0 peak change with the layer thickness.
Lattice parameter as a function of the thickness of the growing layer. The line fitted to the data is an exponential decay function. The inset presents an enlarged plot of the initial phase of the growth. The MnAs films is already fully relaxed at a thickness of . The corresponding error bars are smaller than the symbols.
Williamson-Hall plot in the reciprocal-lattice representation for the Gaussian line profiles. is the reciprocal-lattice vector and , where is the integral breadth of the physically broadened profile.
Average in-plane domain size vs the layer thickness measured in the monolayers (ML) during the growth. The size was calculated according to Eq. (4).
Volume-weighted distribution function (circles) along MnAs [00.1]. The line is a fit by a lognormal function. This function demonstrates the possible fluctuations of the domain sizes.
Some microstructural properties of the 20-nm-thick MnAs layer on GaAs(001). The are the mosaic spreads of the twist angle of the domains obtained directly from the widths of the scans across the 00.2 and the 11.0 diffraction maxima. The average domain sizes and strains along two perpendicular directions in the interface between MnAs and GaAs are calculated from the integral breadths of the physically broadened profiles of the scans. The corresponding correlation parameters of the positions of the dislocations are estimated from a comparison with the theory for the randomly positioned dislocations.
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