COMbining Experiment and theory to model the epitaxial growth of TMDC ON graphene/GeOI – COME_ON

This project concerns an original coupling between experimental investigation of the epitaxy of 2D materials (2DM) with a multi-scale modelling addressing both the equilibrium and non-equilibrium aspects of crystal growth. If the 2DM have already revolutionized the solid-state physics, the classic exfoliation to produce them has intrinsic limitations, and we are interested in the growth mechanisms of their alternative epitaxy. We suggest to investigate the paradigmatic graphene (Gr) system to accommodate the epitaxial growth of the model WSe2, MoSe2 transition metal dichalcogenide (TMDC) that are extensively studied for their outstanding electronic, optical and spintronic properties. We will make use of a promising GeOI buffer layer for decoupling the 2D adlayer from its substrate that will both enable an optimally controlled growth, and allows the use of promising microelectronics wafers. We aim at understanding finely the growth mechanisms in order to control the growth of large-scale Gr-TMDC of high crystalline quality. To do so, experimental investigation will be coupled with a multiscale modelization of the growth, from Angstroms up to micrometers, from femto-seconds up to minutes. We will characterize the diffusion and binding energy barriers with ab-initio calculations, but also local equilibrium configurations. The dynamics will be investigated at atomistic time scales with molecular-ab-initio dynamics and on experimental scales using dedicated kinetic Monte-Carlo (KMC) simulations. The latter will be parameterized according to ab-initio calculations and experimental results, and will be finely tuned to characterize and predict optimal growth regimes. This project gathers experimental and theoretical teams with a unique know-how on state-of-the-art tools and techniques both as regards the growth and characterization of Ge, GeOI, Gr and TMDC (IM2NP, SPINTEC) and the modelization of atomistic up to statistical out-of-equilibrium processes (INSP, LPICM).