Journal of Vacuum Science & Technology B, Vol.18, No.3, 1322-1332, 2000
Highly localized thermal, mechanical, and spectroscopic characterization of polymers using miniaturized thermal probes
In this article, we demonstrate the versatility of use of cantilever-type resistive thermal probes. The probes used are of two kinds, Wollaston wire probes and batch-microfabricated probes. Both types of probe can be operated in two modes: a passive mode of operation whereby the probe acts as a temperature sensor, and an active mode whereby the probe acts also as a highly localized heat source. We present data that demonstrate the characterization of some composite polymeric samples. In particular, the combination of scanning thermal microscopy with localized thermomechanometry (or localized thermomechanical analysis, L-TMA) shows promise. Comparison with data from conventional bulk differential scanning calorimetry shows that inhomogeneities within materials that cannot be detected using conventional bulk thermal methods are revealed by L-TMA, We also describe a new mode of thermal imaging, scanning thermal expansion microscopy. Finally, we outline progress towards the development of localized Fourier transform infrared spectroscopy: here the probe, in this case operated in the temperature-sensing mode, detects the photothermal response of a specimen exposed to the beam and heated thereby.