Systems and Control Approach to Electro-Thermal Sensing

Electro-thermal sensors serve as low-cost, highly integrable deflection sensors in scanning probe applications. They also find application as position sensors for nanopositioning applications. These sensors consist of microfabricated silicon structures with integrated heating elements. The dynamics of these sensors are well captured by a feedback model consisting of a linear thermal system and a non-linear memoryless operator. During sensing, the signal being measured perturbs the thermal system. This perturbation can be analyzed to derive the sensing transfer function. This systems approach is particularly well suited for the experimental identification of electrothermal sensors. Moreover, the sensitivity and bandwidth of these sensors can be further enhanced by external feedback, thus illustrating the applicability of feedback control to shape a sensors sensing dynamics.