Evolution of the Graphene Layer in Hybrid Graphene/Silicon Carbide Heterostructures upon Heating

The hybrid graphene/SiC model is studied via molecular dynamics simulation to observe the evolution of the graphene layer upon heating. A two-layer model containing 10,000 graphene atoms and 7000 SiC atoms is heated from 50 K to 6000 K via Tersoff and Lennard-Jones potentials. The melting point zone is defined as the temperature range from 4400 K to 4600 K, which is close to the melting zone of graphite in an experiment. The Lindemann criterion for the 2D case is calculated and used to observe the appearance of liquid-like atoms. The evolution upon heating is analyzed on the basis of the occurrence/growth of liquid-like atoms, the radial distribution functions, and the formation of clusters. The liquid-like atoms tend to form clusters, and the largest cluster increases in size slightly to form a single largest cluster of liquid-like atoms. Graphic abstract