Experimental Investigation of Scaling Effect on Thermal Transport in Nanoscale Hotspots

This paper reports experimental investigation of the scaling effect on thermal transport in platinum nanoheaters deposited on a single crystalline silicon substrate. The size dependency of the thermal resistances of nanoheaters with dimensions from 5 μm down to 100 nm is experimentally obtained. Additional Joule heating and electrical resistance thermometry in heater/sensor pairs of various dimensions and spacing (100 nm to 400nm) are carried out in order to study the temperature distribution in the vicinity of these nanoheaters. The results of these two sets of measurements confirm that the thermal resistances of smaller nanoheaters are dominated by the interface resistance between the platinum and silicon substrate. Furthermore, analytical solutions of the BTE around a hot spot are used to evaluate and examine the significance of the localized heating or sub-continuum transport around a hotspot.