Magnetic and magneto-transport properties of Ga1−xMnxN grown by MOCVD

The Ga1−xMnxN epitaxial films were grown by metalorganic chemical vapor deposition (MOCVD) with tricarbonyl (methycyclopentadienyl) manganese ((MCP)2Mn) as dopant source. Magnetic measurements indicate that the films are n-type conductivity (x=0.01), ferromagnetic ordering with Curie temperature above room temperature. The magnetic moment per Mn atom decreases when the Mn concentration changes from 0.01 to 0.03. Magneto-transport properties were performed in the temperature range of 2–300 K. The magneto-resistance (MR) changes from negative effect to positive effect with increasing temperature. The negative MR effect at low temperature is due to the reduction of the magnetic scattering of the Mn ions under the applied magnetic field. Furthermore, the zero-field-cooled (ZFC)/field-cooled (FC) and MR behavior at low temperature confirm that the ferromagnetism and paramagnetism coexist in Ga1−xMnxN films.