Using nonequilibrium molecular dynamics, we investigate the mechanisms of thermal transport across SiC/graphene sheets. In simulations, 3C-, 4H-, and 6H-SiC are considered separately. Interfacial thermal resistances between Bernal stacking graphene sheets and SiC (Si- or C-terminated) are calculated at the ranges of 100？K~700？K. The results indicate, whether Si-terminated or C-terminated interface, the interfacial thermal resistances of 4H- and 6H-SiC have similar trends over temperatures. Si-terminated interfacial thermal resistances of 3C-SiC are higher than those of 4H- and 6H-SiC in a wide temperature range from 100？K to 600？K. But, for C-rich interface, this range is reduced from 350？K to 500？K. 1. Introduction For the atomically thin structure of graphene, it has attracted much attention due to potential applications to thermoelectric and photoelectric devices. Over the past decade, researchers mainly focus on the fabrication of graphene and its physical characteristics. The most common used methods of graphene fabrication are epitaxial growth on silicon carbide (SiC) and chemical vapor deposition (CVD). As to epitaxial growth method, Si atoms sublimate from a single-crystal SiC substrate and create large area graphene sheets. CVD method employs carbon source gas to react with the specific substrate chemically, so as to synthesize graphene sheets. In recent years, the techniques of graphene production have been improved dramatically. Tzalenchuk et al. [1] synthesized 50？um2 graphene sheets by epitaxial growth method. Soon after, Bae et al. [2] made graphene films with 762？mm diagonal length onto Cu substrate. In 2011, Zhang et al. [3] first realized the low temperature growth of graphene onto several substrates such as SiC, SiO2, and Al2O3 by plasma enhancement chemical vapor deposition (PECVD). Through solid-state molecular beam epitaxy (SSMBE), Tang et al. [4] made graphene films grown on Si(111) substrate and analyzed the effects of SiC buffer layer on stabilizing the surface of Si substrate. Janssen et al. [5–7] investigated the Hall resistance in epitaxial graphene grown on Si-terminated SiC and other graphene material systems. At present, although numerous studies have demonstrated the high thermal conductivities of graphene and graphene sheets along tangent direction, little work has been done to address the characteristics of graphene sheets along normal direction, let alone SiC/graphene composite films. 2. Theory As to theoretical study, researchers usually adopt analytical or numerical approaches to perform nanoscale heat transport
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