An Alternating-Current Voltage Modulated Thermal Probe Technique for Local Seebeck Coefficient Characterization

An ac voltage-modulated thermal probe technique based on the atomic force microscope is developed to measure local Seebeck coefficients (S) of thermoelectric bulk and films. The characterization principle is based on the strictly quadratic relationship between the excited local dc Seebeck voltage and the applied ac voltage at high frequency. Excellent agreement is found between local S values and their corresponding macro-S values of thermoelectric bulk and thin films. This thermoelectric probe technique provides a very convenient, promising tool for local thermoelectric parameters with sub-micrometer scale resolution.