Control of the crystal orientation of zinc-blende MnTe epitaxial films grown on GaAs

Epitaxial films of the zinc-blende MnTe have been successfully grown directly on (001) GaAs substrates by molecular beam epitaxy. The structure and the stoichiometry of the GaAs substrate surfaces are found to be important in determining the orientation and the twin formation of the MnTe films. When the preheating treatment of the substrate was done at 580 °C and reflection high energy electron diffraction (RHEED) from the GaAs surface showed (3×1) reconstruction pattern during the treatment, the twin-free (111) oriented MnTe was obtained on it. When the preheating treatment was done at 560 °C, the weak streaked RHEED pattern with a halo was observed from the GaAs surface and the (001) oriented MnTe was obtained on it.