On Local Thermal Conductivity Measurement by the SThM

Abstract

Comprehensive study on the quantitative local thermal conductivity measurement with a thermal conductance and contact temperature combination method by the scanning thermal microscope (SThM) was conducted. The micro cantilever probe including heater, thermocouple, thermopile and electrode for contact thermocouple, and the sample preparation method of coating gold thin film as another electrode of the contact thermocouple were developed. The experiment in the force curve mode to gold and glass regions showed that heat flow and contact temperature are simultaneously measured as varying a contact load, and that the method detects difference in thermal conductivity between the two regions. Numerical simulation of the contact region by thermal conduction model shows that conductance of the flat body with the thin film is described as the combination of conductance near the contact region, one in the film and one in the body. Reasonableness and a perspective of the method were also discussed through analyzing a derivation method of conductivity and a spatial resolution of the method