Structure and morphology of 2H-MoTe2 monolayer on GaAs(111)B grown by molecular-beam epitaxy

<jats:title>Abstract</jats:title><jats:p>The structure and morphology of monolayer 2H-MoTe<jats:sub>2</jats:sub> on GaAs(111)B grown by molecular-beam epitaxy have been studied using scanning tunneling microscopy, electron diffraction, and X-ray photoelectron spectroscopy. The MoTe<jats:sub>2</jats:sub> film grown and annealed under the Te-rich condition is mainly composed of a pure 2H phase, while, under the Te-deficient conditions, the 2H-MoTe<jats:sub>2</jats:sub> phase begins to evolve into nanowire-like structures owing to the desorption of Te. The 2H-MoTe<jats:sub>2</jats:sub>(0001) film on GaAs(111)B exhibits two types of energetically favorable epitaxial orientations; one is a perfect alignment of [11<jats:inline-formula><jats:alternatives><jats:tex-math>$$\overline{2}$$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mover> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> <mml:mo>¯</mml:mo> </mml:mover> </mml:math></jats:alternatives></jats:inline-formula>0]MoTe<jats:sub>2</jats:sub> // [1<jats:inline-formula><jats:alternatives><jats:tex-math>$$\overline{1}$$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mover> <mml:mrow> <mml:mn>1</mml:mn> </mml:mrow> <mml:mo>¯</mml:mo> </mml:mover> </mml:math></jats:alternatives></jats:inline-formula>0]GaAs, and the other shows a slight in-plane rotation of ± 0.77<jats:sup>∘</jats:sup>, which reduces the effective lattice mismatch between MoTe<jats:sub>2</jats:sub> and GaAs.</jats:p>