Modeling and Characterization of Adapted 3$\omega$-Method for Thermal Conduction Measurement of Thermal Radiation Sensors

In this letter, a thermal conduction measurement method for thermal radiation sensors, such as vacuum-packaged bolometers, is presented. The idea of the method is deduced from the classical 3ω-method proposed by Cahill [1]. Here, the measurement geometry is a complete sensor geometry, which is suspended from the substrate by thermal isolation legs. The most relevant performance factor for such a sensor is the thermal isolation; this is why the thermal conduction measurement is so important to design better sensors. Additionally, the thermal loss mechanisms need to be investigated because the sensors are normally operated at the thermal radiation limit. Therefore, these loss mechanisms are modeled with an electrothermal equivalent circuit of the whole measurement setup. The measurement method is then used to measure and derive the thermal conduction of known single microbolometer structures.