A MICROMACHINED RESONANT LOW-PRESSURE SENSOR USING AN ISLAND-DIAPHRAGM STRUCTURE

This paper presents a micromachined resonant low-pressure sensor using an island-diaphragm structure. With the inclusion of the island-diaphragm structure, low pressure under measurement can be translated to the frequency shifts of resonators under the condition that vibration modes of resonators and the pressure-sensitive diaphragm can be effectively separated. Numerical simulations were conducted, confirming that the developed resonant low-pressure sensor can work properly in the measurement range without modal interference due to the island-diaphragm structure. Experimental characterization produced 1) quality factors higher than 30000, implying no modal interference between resonators and the pressure sensitive diaphragm; 2) a sensitivity of 12.375 Hz/Pa, indicating that the low-pressure sensor developed in this study can function well in the measurement range of 0-1 kPa, validating the functionality of the island-diaphragm structure.