With the progress of GaN devices, ScN has attracted much attention in the recent decade. As 111-orieted ScN is lattice-matched to 0001 oriented wurtzite GaN, ScN is a potential material for development of GaN devices. In this study, the ScN films were grown on (100) MgO single crystals by a MBE method, and the electric properties of MBE grown ScN films were measured by temperature dependence Hall effect. The effect of the growth condition, the Sc/N ratio, growth temperature and nitrogen-radical state, on the electric properties of ScN films was studied.

ScN films were prepared by MBE using an RF plasma discharge cell as the nitrogen source. A conventional K-cell was used for evaporation of Sc metal. The K-cell temperature was varied from 1270–1310°C to examined the effect of Sc-flux on the surface morphology and the electric properties. A nitrogen radical beam, generated by the RF discharge cell, was irradiated on the film surface. MgO single crystals with a well polished (100) face were used for the substrates of ScN films. Before the growth, the substrates were thermally cleaned in a vacuum at 850°C for 30 min. The growth temperature was varied between 300 and 850°C to evaluate the effect of the substrate temperature. The crystalline phase and lattice orientation of the films were determined from XRD measurements. The surface of the films were observed by an AFM. The electric resistivity, the carrier concentration and the Hall mobility of the films were measured by Hall effect at 80–400K.

The ScN films were grown epitaxially on the MgO (100) substrates. Hall coefficient measurement confirmed that the ScN films grown under N-rich condition were highly degenerate n-type semiconductor, and the carrier concentration of the ScN films were 10¹⁹–10²¹ cm^-3, and the Hall mobility were 50–150 cm²·V^-1·s^-1 even as the undoped films. The carrier concentration and the Hall mobility of the ScN film were sensitive to the growth temperature and the nitrogen-radical state compared to the Sc/N supplying ratio during the deposition, and the Hall mobility of the ScN films increased with increasing carrier concentration. The temperature-dependence Hall coefficient measurement revealed that the carrier concentration is nearly independent of temperature, indicating that the change of the resistivity with temperature is explained by the change of the Hall mobility. The Hall mobility of the ScN films increased with decreasing the measurement temperature, and the decrease of the Hall mobility at the lower temperature region due to ionized impurity scattering was not observed in temperature range from 80-400K.

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