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The structure of a ZnSnAs2 thin film epitaxially grown on an InP substrate was evaluated using x-ray fluorescence holography. The reconstructed three-dimensional atomic images clearly show that the crystal structure of the ZnSnAs2 thin film is mainly of the sphalerite type, in contrast to the bulk form. A large disordering of the As layers is observed, whereas the positions of the Zn/Sn atoms are relatively stable. The analysis of the data indicates that the As layers serve as a buffer and relax the strain caused by the random occupation of Zn and Sn atoms. These results provide further understanding and a means of controlling the growth of Mn-doped ZnSnAs2, a high-Tc diluted magnetic semiconductor.

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ZnSnAs 2 thin films were prepared by molecular beam epitaxy (MBE) on semi-insulating (001) InP substrates using the same growth conditions as previously reported. High-resolution X-ray diffractometry (HRXRD) and Raman spectroscopy studies suggest the presence of both the chalcopyrite and sphalerite phases. The transport properties were measured from 5 K up to room temperature. We observed a pronounced peak in the Hall coefficient temperature dependence curve at $130 K, similar to those observed only from chalcopyrite-phase bulk ZnSnAs 2 in earlier studies. A hole concentration of p ¼ 5:98 Â 10 18 cm À3 , hole mobility of ¼ 23:61 cm 2 /(VÁs) and resistivity of ¼ 4:43 Â 10 À2 Ácm were obtained at room temperature.

We present for the first time the temperature dependence of resistivity, anomalous Hall effect, and extraordinary magnetoresistance (MR) in 6.5% Mn-doped ZnSnAs2 epitaxial film prepared by molecular beam epitaxy (MBE) on InP(001) substrates. The magnetic field dependence of magnetization (M–H curve) show clear hysteresis loops at 300 K for magnetic fields applied both perpendicular and parallel to the sample surface. The Curie temperature was evaluated to be 350 K. Near-zero-field hysteresis loops in the anomalous Hall resistance were also observed at various temperatures corresponding to the hysteretic out-of-plane magnetization of the sample. Negative and positive values of MR were observed in the low-field region. The behavior of the MR can be properly described by the Khosla–Fischer semi-empirical model for spin scattering of carriers in an impurity band. These characteristics strongly indicate a carrier-spin interaction in Mn-doped ZnSnAs2.