Journal of Micromechanics and Microengineering · 2011 · 33 citations · 23 references
EngineeringElectrical EngineeringMaterials ScienceHeat TransferMicroelectromechanical SystemsSensorsElectrostatic ActuationMems DesignMems FabricationMems SensorsMicroelectromechanical SensorsThermal SensorsConductive Heat TransferDisplacement Sensor ResolutionDisplacement Sensor SensitivityLumped Capacitance ModelingMems Thermal SensorsSensor ResolutionSensor SensitivitySilicon-on-insulator Technology
The study introduces a MEMS displacement sensor that uses conductive heat transfer from a resistively heated silicon structure to a parallel actuated stage, aiming to optimize sensitivity through a lumped capacitance model. The sensor is a differential design fabricated on a silicon‑on‑insulator platform within a single mask alongside electrostatic actuators and flexure stages, with sensitivity tuned by adjusting doping, temperature, heater dimensions, and a lumped capacitance model. Experimental results show the sensor achieves a 2 nm resolution over a 25 Hz bandwidth with a full‑scale range of 110 µm.
This work presents a MEMS displacement sensor based on the conductive heat transfer of a resistively heated silicon structure towards an actuated stage parallel to the structure. This differential sensor can be easily incorporated into a silicon-on-insulator-based process, and fabricated within the same mask as electrostatic actuators and flexure-based stages. We discuss a lumped capacitance model to optimize the sensor sensitivity as a function of the doping concentration, the operating temperature, the heater length and width. We demonstrate various sensor designs. The typical sensor resolution is 2 nm within a bandwidth of 25 Hz at a full scale range of 110 µm.
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