Molecular Beam Epitaxy growth of MoTe 2 on Hexagonal Boron Nitride

, 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 2 , MoS 2 or WSe 2 . Here, we present for the first time the molecular beam epitaxy growth of MoTe 2 on atomically smooth hexagonal boron nitride (hBN) substrate. Occurrence of MoTe 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 2 grown in a single monolayer regime enable us to observe impact of growth conditions on formation of various structures: flat grains, net of one-dimensional structures, quasi continuous monolayers with bilayer contribution. Comparison of the distribution of the thickness with Poisson distribution shows that tested growth conditions fa-vorites formation of grains with monolayer thickness. The diffusion constant of MoTe 2 grown on hBN can reaches order of 10 − 6 cm 2 /s for typical growth conditions. Raman spectroscopy results suggest a coexistence of various phases with domination of 2H MoTe 2 for samples grown at lower temperatures. XPS measurements confirms the stoichiometry of MoTe 2 .

[1]  M. Tokarczyk,et al.  Heteroepitaxial Growth of High Optical Quality, Wafer-Scale van der Waals Heterostrucutres , 2021, ACS applied materials & interfaces.

[2]  K. Korona,et al.  Charge transport in MBE-grown 2H-MoTe2 bilayers with enhanced stability provided by an AlOx capping layer. , 2020, Nanoscale.

[3]  C. Merckling,et al.  On the van der Waals Epitaxy of Homo-/Heterostructures of Transition Metal Dichalcogenides. , 2020, ACS applied materials & interfaces.

[4]  K. T. Law,et al.  Highly Tunable Nonlinear Hall Effects Induced by Spin-Orbit Couplings in Strained Polar Transition-Metal Dichalcogenides , 2019, Physical Review Applied.

[5]  T. Woźniak,et al.  Hidden spin-polarized bands in semiconducting 2H-MoTe2 , 2020 .

[6]  R. Sporken,et al.  Substrate temperature dependence of the crystalline quality for the synthesis of pure-phase MoTe2 on graphene/6H-SiC(0001) by molecular beam epitaxy , 2019, Nanotechnology.

[7]  Tuo-Hung Hou,et al.  Polymorphism Control of Layered MoTe2 through Two-Dimensional Solid-Phase Crystallization , 2019, Scientific Reports.

[8]  Sung Kim,et al.  Two-dimensional phase-engineered 1T′– and 2H–MoTe2-based near-infrared photodetectors with ultra-fast response , 2019, Journal of Alloys and Compounds.

[9]  Sui-lin Liu,et al.  Molecular Beam Epitaxy Scalable Growth of Wafer‐Scale Continuous Semiconducting Monolayer MoTe2 on Inert Amorphous Dielectrics , 2019, Advanced materials.

[10]  M. Terrones,et al.  Defect-Controlled Nucleation and Orientation of WSe2 on hBN: A Route to Single-Crystal Epitaxial Monolayers. , 2019, ACS nano.

[11]  H. Zhang 张,et al.  Electronic structure of molecular beam epitaxy grown 1 T ′ -MoTe2 film and strain effect , 2019 .

[12]  Z. Sheng,et al.  Planar Hall effect in the type-II Weyl semimetal Td−MoTe2 , 2018, Physical Review B.

[13]  A. Dimoulas,et al.  Direct Observation at Room Temperature of the Orthorhombic Weyl Semimetal Phase in Thin Epitaxial MoTe2 , 2018, Advanced Functional Materials.

[14]  Lin Zhou,et al.  Thermodynamics and Kinetics Synergetic Phase-Engineering of Chemical Vapor Deposition Grown Single Crystal MoTe2 Nanosheets , 2018 .

[15]  Chaofan Zhang,et al.  Electronic structure of monolayer 1T′-MoTe2 grown by molecular beam epitaxy , 2018 .

[16]  Moon J. Kim,et al.  Defects and Surface Structural Stability of MoTe2 Under Vacuum Annealing. , 2017, ACS nano.

[17]  E. Reed,et al.  Structural phase transition in monolayer MoTe2 driven by electrostatic doping , 2017, Nature.

[18]  Moon J. Kim,et al.  New Mo6Te6 Sub‐Nanometer‐Diameter Nanowire Phase from 2H‐MoTe2 , 2017, Advanced materials.

[19]  D. Fu,et al.  Large Area Synthesis of 1D‐MoSe2 Using Molecular Beam Epitaxy , 2017, Advanced materials.

[20]  Jin-an Shi,et al.  Precisely Aligned Monolayer MoS2 Epitaxially Grown on h-BN basal Plane. , 2017, Small.

[21]  C. Felser,et al.  Signature of type-II Weyl semimetal phase in MoTe2 , 2016, Nature Communications.

[22]  Moon J. Kim,et al.  New Mo 6 Te 6 Sub-Nanometer-Diameter Nanowire Phase from 2H-MoTe 2 , 2017 .

[23]  Y. Sun,et al.  Extremely large magnetoresistance in the type-II Weyl semimetal Mo Te 2 , 2016, 1706.03356.

[24]  Timur K. Kim,et al.  Fermi Arcs and Their Topological Character in the Candidate Type-II Weyl Semimetal MoTe 2 , 2016, 1604.08228.

[25]  Moon J. Kim,et al.  Controllable growth of layered selenide and telluride heterostructures and superlattices using molecular beam epitaxy , 2016 .

[26]  S. Banerjee,et al.  Structural and Electrical Properties of MoTe2 and MoSe2 Grown by Molecular Beam Epitaxy. , 2016, ACS applied materials & interfaces.

[27]  Yunseok Kim,et al.  Room Temperature Semiconductor-Metal Transition of MoTe2 Thin Films Engineered by Strain. , 2016, Nano letters.

[28]  A. Liao,et al.  Large-Area Synthesis of High-Quality Uniform Few-Layer MoTe2. , 2015, Journal of the American Chemical Society.

[29]  Suyeon Cho,et al.  Phase patterning for ohmic homojunction contact in MoTe2 , 2015, Science.

[30]  L. Assmann,et al.  X-ray photoelectron spectroscopy study of MoTe2 single crystals and thin films , 2003 .

[31]  Evans,et al.  Scaling analysis of diffusion-mediated island growth in surface adsorption processes. , 1992, Physical review. B, Condensed matter.

[32]  Kleiner,et al.  Activation energy for surface diffusion of Si on Si(001): A scanning-tunneling-microscopy study. , 1991, Physical review letters.