Frequency-multiplexed combinatory mass sensing with single data line from multiple integrated film bulk acoustic resonators

This paper presents a novel array of four film bulk acoustic resonators (FBAR) having four distinct fundamental resonant frequencies that offers parallel and/or combinatory mass sensing of multiple chembio species, such as various proteins. To achieve the multiple resonant frequencies, we connect multiple FBARs (having slightly different resonant frequencies, thus each representing a unique sensor) in parallel, and form one FBAR (out of the multiple) on a chip. This way, when we measure the frequency shifts of the arrayed FBAR through a network analyzer, we have multiple resonant frequencies, each of which will change as a function of added mass (of chembio species), independent of the others.