CMOS Compatible Aluminium Nitride Solidly Mounted Resonator with an Integrated Microheater for Temperature Modulation

The increase in air pollution and its effect on human health, is highlighting a growing demand for ubiquitous low-cost air quality monitors. Acoustic resonators have significant potential to satisfy this need. Solidly mounted resonators (SMR) are of special interest, because they have the advantage of being small and can be integrated into smart CMOS systems for air quality monitoring. This paper presents a CMOS-based SMR with a resonant frequency of about 2 GHz and a Q-factor of ca 200. The device comprises an integrated microheater with multi-purpose potential for temperature frequency modulation, temperature control, enhanced device sensitivity, sensor self-cleaning and use of single sensor as a virtual sensor array.