(438d) Characterizing Thermal Transport in Self Assembled Monolayer Junctions

Our investigation involves studies of the thermal transport properties of a single organic-inorganic interface – a self-assembled monolayer (SAM) junction. Molecular junctions have generated excitement as potential forerunners in organic electronics and are fundamental to the development of new hybrid materials. Characterization of their thermal properties is important in understanding how they will dissipate heat, a parasitic byproduct in their application in electronics and energy conversion. Accurate quantification of their thermal conductance, which describes this behavior, is thus essential.

Complementary experimental and computational approaches will address a prototypical Au-SAM-Au interface, where an alkane based SAM is initially considered.  Molecular dynamics simulations are being implemented to model and study the effect of molecule length, choice of leads and other factors affecting bonding between the organic and inorganic components. Independent experimental measurements on transfer printed leads on SAMs are being performed using frequency domain thermoreflectance – a laser-based non-contact measurement technique. Initial measurements indicate that the Au-SAM-Au interface has a higher conductance than previously studied SAM interfaces, perhaps because prior measurements considered SAMs sandwiched between dissimilar contacts. Hence, this work is novel because the contacts are identical, and the interface conductance can be directly related to the SAM properties. This study is thus expected to provide a detailed picture on the thermal transport phenomenon across such interfaces.