Fundamentals of Micro-mechanical Thermo-electric Sensors

The thermal and electrical properties of a thin heater strip made of Silicon, consisting of a lowdoped electrical resistor connected to highly doped long legs, are discussed based on analytical models for the heat and the electrical current transport. Such heater strips are used for example as sensitive position and hight sensors in local probe storage applications. The aim of the paper is to provide a thorough understanding of the important physical mechanisms and scaling laws, and thus to provide a solid basis for directed engineering of such sensors. In particular, the dynamic response is treated in full generality including the intricate electro-thermal coupling arising from the highly temperature dependent resistivity of the Si heater element.