Assessment of the Absolute Mass Attachment to an AlN-Based Solidly Mounted Resonator Using a Single Shear Mode

摘要

We prove the ability of a gravimetric sensor consisting in an AlN-based solidly mounted resonator (SMR) operating in the shear mode to decouple mass detection from temperature variations. This is achieved by simultaneously monitoring both the resonant and antiresonant frequency of the shear mode during a detection experiment subjected to temperature variations. These resonant and antiresonant frequencies have similar mass sensitivities (2485 Hz cm(2)g) but different temperature coefficients of frequency (TCFr = -7.9 ppm/degrees C and TCFa = -11 ppm/degrees C), which allows us to correct the influence of temperature on the value of the detected mass in the ng range. This technique suppresses the need of using TCF compensation methods or integrated heaters to maintain the temperature of the sensor constant.