Abstract
A miniaturized, integrated sensor chip for barometric pressure measurement is desired to be deployed for mobile applications. In this work, a capacitive pressure sensor operated based on the elastic squeeze-film damping effect is implemented in a CMOS (complementary metal oxide semiconductor) process to provide convenient signal transduction and excellent sensitivity. Post-CMOS fabrication of the aluminum/silicon dioxide microstructure is convenient as the sensor operation does not require a sealed reference cavity. Compared to prior CMOS micromachined sensors [1], this work demonstrates a better sensitivity of 5.3 Hz/Pa improved by nearly 7X, and a smaller resonant plate size of 100times 100 mumathrm{m}-{2} reduced by 4X.