Manipulating Thermal Conductance at Metal–Graphene Contacts via Chemical Functionalization

Abstract

Graphene-based devices have garnered tremendous attention due to the unique physical properties arising from this purely two-dimensional carbon sheet leading to tremendous efficiency in the transport of thermal carriers (i.e., phonons). However, it is necessary for this two-dimensional material to be able to efficiently transport heat into the surrounding 3D device architecture in order to fully capitalize on its intrinsic transport capabilities. Therefore, the thermal boundary conductance at graphene interfaces is a critical parameter in the realization of graphene electronics and thermal solutions. In this work, we examine the role of chemical functionalization on the thermal boundary conductance across metal/graphene interfaces. Specifically, we metalize graphene that has been plasma functionalized and then measure the thermal boundary conductance at Al/graphene/SiO(2) contacts with time domain thermoreflectance. The addition of adsorbates to the graphene surfaces are shown to influence the cross plane thermal conductance; this behavior is attributed to changes in the bonding between the metal and the graphene, as both the phonon flux and the vibrational mismatch between the materials are each subject to the interfacial bond strength. These results demonstrate plasma-based functionalization of graphene surfaces is a viable approach to manipulate the thermal boundary conductance.

Qualitative link between work of adhesion and thermal conductance of metal/diamond interfaces

“…A similar trend has been reported on the Al/graphene interface 33 . H has been shown to diminish the adhesion force between diamond and aluminum 30 .…”

Influence of diamond surface termination on thermal boundary conductance between Al and diamond

“…Collins et al 9 found that oxygenation and hydrogenation of diamond change the TBC between Al and diamond, to higher values for the former and lower for the latter. Finally, Hopkins et al 10 recently reproduced this result with graphene instead of diamond and observed the same trends as Collins et al. In this paper, we extend the work by Collins et al 9 and we present a thorough investigation of the effect of various surface treatments on the Al/diamond TBC.…”

A review on the role of interface in mechanical, thermal, and electrical properties of polymer composites

“…Therefore, the interfacial zones predominantly affect the thermal conductivity of the composite [245,246]. As a result, anything that can affect the interfacial regions (e.g., geometry of particles [247][248][249][250][251][252][253], aggregation [254][255][256], interfacial pressure [257], roughness [258][259][260], and the strength of interactions at the interfaces [261][262][263][264][265]) in the composites would influence their thermal conductivity. In this section, we will review the parameters affecting the interfacial interactions and their subsequent impact on the thermal conductivity of the composites.…”