Microthermal analysis
Encyclopedia
Microthermal analysis is a materials characterization technique which combines the thermal analysis
principles of differential scanning calorimetry
(DSC) with high spatial resolution of scanning probe microscopy
. The instrument consists of a thermal probe which is basically a fine platinum/rhodium alloy wire (5 micro meter in diameter) coated by a sheath of silver (Wollaston wire
). The wire is bent into V-shape and the silver sheath is etched away to form a fine pointed tip. The probe acts as both the heater as well as temperature sensor. The probe is attached to a conventional scanning probe microscope and can be scanned over the sample surface to spatially resolve the thermal behavior of the sample.
This technique has been widely used for localized thermal analysis, where the probe is heated rapidly to avoid thermal diffusion through the sample and the response of the substance in immediate proximity to the tip is measured as a function of temperature.
Thermal analysis
Thermal analysis is a branch of materials science where the properties of materials are studied as they change with temperature. Several methods are commonly used - these are distinguished from one another by the property which is measured:...
principles of differential scanning calorimetry
Differential scanning calorimetry
Differential scanning calorimetry or DSC is a thermoanalytical technique in which the difference in the amount of heat required to increase the temperature of a sample and reference is measured as a function of temperature. Both the sample and reference are maintained at nearly the same temperature...
(DSC) with high spatial resolution of scanning probe microscopy
Scanning probe microscopy
Scanning Probe Microscopy is a branch of microscopy that forms images of surfaces using a physical probe that scans the specimen. An image of the surface is obtained by mechanically moving the probe in a raster scan of the specimen, line by line, and recording the probe-surface interaction as a...
. The instrument consists of a thermal probe which is basically a fine platinum/rhodium alloy wire (5 micro meter in diameter) coated by a sheath of silver (Wollaston wire
Wollaston wire
Wollaston wire is a very fine platinum wire clad in silver and used in electrical instruments. For most uses, the silver cladding is etched away by acid to expose the platinum core.- History :...
). The wire is bent into V-shape and the silver sheath is etched away to form a fine pointed tip. The probe acts as both the heater as well as temperature sensor. The probe is attached to a conventional scanning probe microscope and can be scanned over the sample surface to spatially resolve the thermal behavior of the sample.
This technique has been widely used for localized thermal analysis, where the probe is heated rapidly to avoid thermal diffusion through the sample and the response of the substance in immediate proximity to the tip is measured as a function of temperature.