SCANNING PROBE MICROSCOPY FOR THERMAL TRANSPORT MEASUREMENTS

Understanding energy transport and dissipation in nanoscale devices is of increasing importance. Novel transport and dissipation phenomena are expected to arise in these devices as the characteristic dimensions become comparable to the wavelength, coherence length, and mean free path (MFP) of charge and energy carrierselectrons and phonons. Of particular importance are irreversible processes that occur in all nanoscale devices under nonequilibrium conditions and are associated with Joule heating and resultant temperature gradients. Therefore, the ability to measure local temperatures with nanometer resolution is critical for characterizing and understanding irreversibility, heat dissipation, and transport in nanoscale devices. A novel approach for high-resolution characterization of temperature fields is scanning thermal microscopy (SThM), which leverages special scanning probes with integrated temperature sensors. This review discusses various SThM techniques and highlights recent advances in ultra-high-vacuum SThM techniques for quantitative nanoscale thermometry. Further, we discuss applications of SThM to the elucidation of energy transport and dissipation in functional devices as well as prototypical low-dimensional devices.