Hexagonal boron nitride has already been proven to serve as a decent substrate for high quality epitaxial growth of several 2D materials, such as graphene, MoSe$_{ \tiny{ \textrm{ 2}}}$, MoS$_{ \tiny{ \textrm{ 2}}}$ or WSe$_{ \tiny{ \textrm{ 2}}}$. Here, we present for the first time the molecular beam epitaxy growth of MoTe$_{ \tiny{ \textrm{ 2}}}$ on atomically smooth hexagonal boron nitride (hBN) substrate. Occurrence of MoTe$_{ \tiny{ \textrm{ 2}}}$ in various crystalline phases such as distorted octahedral 1T' phase with semimetal properties or hexagonal 2H phase with semiconducting properties opens a possibility of realisation of crystal-phase homostructures with tunable properties. Atomic force microscopy studies of MoTe$_{ \tiny{ \textrm{ 2}}}$ grown in a single monolayer regime enable us to determine surface morphology as a function of the growth conditions. The diffusion constant of MoTe$_{ \tiny{ \textrm{ 2}}}$ grown on hBN can be altered 5 times by annealing after the growth, reaching about 5 $\cdot$ 10$^{ -6}$ cm$^{ 2}$/s. Raman spectroscopy results suggest a coexistence of both 2H and 1T' MoTe$_{ \tiny{ \textrm{ 2}}}$ phases in the studied samples.
Categories: cond-mat.mtrl-sci