Heat Conduction across Monolayer and Few-Layer Graphenes

Abstract

We report the thermal conductance G of Au/Ti/graphene/SiO(2) interfaces (graphene layers 1 ≤ n ≤ 10) typical of graphene transistor contacts. We find G ≈ 25 MW m(-2) K(-1) at room temperature, four times smaller than the thermal conductance of a Au/Ti/SiO(2) interface, even when n = 1. We attribute this reduction to the thermal resistance of Au/Ti/graphene and graphene/SiO(2) interfaces acting in series. The temperature dependence of G from 50 ≤ T ≤ 500 K also indicates that heat is predominantly carried by phonons through these interfaces. Our findings suggest that metal contacts can limit not only electrical transport but also thermal dissipation from submicrometer graphene devices.

Role of Remote Interfacial Phonon (RIP) Scattering in Heat Transport Across Graphene/SiO2 Interfaces

“…15 We thus approximate g RIP  0.02 W m -1 K -1 for heat transfer by RIP scattering in the experiments of Baloch et al 11 To compare these CNT results with our VMTR measurements on graphene interfaces, we 12,13,27 and ~0.004 W m -1 K -1 for the multi-wall CNT interfaces. 15 There are two possible explanations for the different behaviour in graphene and CNTs.…”

“…We measured the thermal conductance G of SiO 2 /graphene/SiO 2 interfaces by the differential time-domain thermoreflectance (TDTR); details of our approach are described in Ref. 13. We find that G ≈ 41 MW m -2 K -1 , with an uncertainty of ~28%.…”

“…The measured thermal conductance is roughly half of G = 83 MW m -2 K -1 for single SiO 2 /graphene interface, 12 consistent with our previous conclusion that for heat conduction, graphene interfaces can be regarded as two discrete interfaces acting in series, even for monolayer graphene. 13 We measured the change of thermal conductance of graphene interfaces under electrostatic fields by a new technique called voltage-modulated thermoreflectance (VMTR). VMTR is an extension of time-domain thermoreflectance (TDTR), a pump-probe technique to study thermal energy transport in nanostructures [19][20][21] and across interfaces.…”

Thermal conductivity of graphene mediated by strain and size

“…Therefore, for suspended samples with the system sizes of several hundreds of microns or less, boundary scattering will significantly limit the thermal conductivity, and the calculated k will increase significantly with increasing system size as demonstrated by the length dependent k shown in Fig. 4(b) 14 corresponding to the case =0,W  . We note that the jump in k at ~4 cm in Fig.…”

Thermal and mechanical improvement of aluminum open-cells foams through electrodeposition of copper and graphene

“…This approximation is valid for both the nanoparticles studied (G2N, G3N), because neither the cross-plane conductance nor R B reveals a strong dependence on the thickness of FLG or the nature of the metal substrate [40,41]. Therefore, the thermal resistance of the coating can be expressed by the following equation:…”