Modelling for the thermal characterization of solid materials by dc scanning thermal microscopy

Abstract

The thermal investigation of matter by use of a very localized heat source, scanning thermal microscopy (SThM), permits materials to be probed at the level of very small subsurface volumes. Therefore, the technique appears to be a promising method to study the thermal properties of thin films of submicrometric thickness. In order to estimate this possibility, we propose a new prediction modelling of the measurement with a SThM based on a hot anemometer wire probe used in a dc regime. From this modelling, a study of the sensitivity of measurement to various parameters operating in the thermal interaction between the probe and a mono-layered sample is presented. It gives new data allowing a better understanding of measurements. A new method to calibrate the technique for thermal conductivity measurement with more accuracy is deduced from this study. New data about the different physical mechanisms governing the probe–sample thermal interaction are given. The proposed approach also supplies a method for the determination of the depth resolution of a thermal probe. This last parameter is essential in the framework of thin film study with a given probe. Its dependence on sample thermal conductivity and thermal coupling area are discussed. Our results specify the possibilities of the technique and should contribute to a more accurate determination of thin film thermal conductivity in its dc regime.

Subsurface imaging of two-dimensional materials at the nanoscale

“…9,10,11 Finally, in Scanning Thermal Microscopy (SThM), the thermal dissipation depends to a great extent on a given volume located under the tip and any non-homogeneity can be thus probed. 12, 13,14 A chapter on its own deserves subsurface imaging through the detection of the elastic properties of materials. Ultrasonic Force Microscopy (UFM) is a technique invented by Kolosov and Yamanaka,15 resulting from an adaption of Atomic Force Microscopy (AFM) working in Contact Mode (CM).…”

Two omega method for active thermocouple microscopy

“…Compared to a thermocouple junction, the advantage of a resistive scanning thermal microscopy ͑SThM͒ probe remains its active mode of operation, which is still extensively studied. [5][6][7][8][9] The well known 3 method offers a direct way to extract a temperature component in ac mode of operation but the thermal signal is integrated all along the heated part of the probe. As a result, this method is not suited to point contact measurements.…”

Methods for topography artifacts compensation in scanning thermal microscopy

“…A finite element analysis was used to solve the Poisson equation related to diffusive heat transfer in the system, which is one of the popular approaches for SThM modeling in a diffusive regime [3,10].…”