An Enhanced High-Sensitivity Micro Resonant Thermometer with Axial Strain Amplification Effect

Abstract

This paper presents an enhanced high-sensitivity micro resonant temperature sensor with axial stain amplification structure. With the external temperature variation, an amplificated axial strain of micro-resonator vibration beam will be produced because of the materials with different thermal expansion coefficients of the micro resonator and package. This will result in a larger resonant frequency shift of the device with temperature change. The theory and analysis of frequency variation is illustrated with temperature sensitivity achieving 309Hz/K. Experimental test shows that actual frequency variation with temperature change of 20K is about 252Hz/K. Simulation match with measurement moderately and can be utilized to optimally design high-sensitivity temperature sensor before the costly fabrication.