Molecular Beam Epitaxial Growth of Indium Telluride on Graphene

Van der Waals heterostructures have attracted great research attention due to their novel electronic structures and their potential in device development and applications. Especially, graphene has aroused significant interest in the study of two-dimensional layered materials with tunable electronic and optical properties. [1] In addition, metallic chalcogenides have shown great potential in optoelectronics and thermoelectric devices. [2] Therefore, epitaxy of graphene/metal chalcogenide layered materials with high quality is an important step in understanding underlying science and application based on two-dimensional materials. [3] In this study, we report high-quality, crystalline indium telluride grown on graphene by molecular beam epitaxy (MBE). This study systematically explores the growth mechanism and structural analysis of graphene/indium telluride mainly using transmission electron microscopy (TEM).<br/> Electron diffraction pattern and atomic resolution STEM images were used to identify the phases of indium telluride and local atomic configurations. Additionally, in order to inspect the epitaxial relation of indium telluride on graphene, both in-plane and cross-sectional HR-TEM images of indium telluride clusters were obtained. Various phases of indium telluride were observed depending on the growth temperature and In/Te flux ratio, which was compared with thermodynamic calculations. The growth behavior of these heterostructures may offer great potential for science and engineering based on atomically thin two-dimensional materials.<br/><br/>References<br/>[1] A. H. Castro Neto et al. “The electronic properties of graphene” <i>Rev. Mod. Phys.</i> 81 109 (2009)<br/>[2] M. Alsalama et al. “Enhancement of thermoelectric properties of layered chalcogenide materials” <i>Rev. Adv. Mater. Sci.</i> 59 371 (2020)<br/>[3] W. Huang et al. “2D layered group IIIA metal chalcogenides: synthesis, properties and applications in electronics and optoelectronics” <i>CrystEngComm</i> 18 3968 (2016)