Quantum 1/f effect in resonant biochemical piezoelectric and MEMS sensors

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 52; no. 9; pp. 1461 - 1467
• Main Authors: Handel, P.H., Tournier, A., Henning, B.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.09.2005; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acoustic sensors; Acoustic signal detection; Acoustics; Biological and medical sciences; Biosensors; Biotechnology; Chemical and biological sensors; Exact sciences and technology; Excitation; Fluctuations; Frequency; Fundamental and applied biological sciences. Psychology; Fundamental areas of phenomenology (including applications); General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Magnetic resonance; Magnetostriction; Methods. Procedures. Technologies; Microelectromechanical systems; Micromechanical devices; Nanostructure; Physics; Piezoelectricity; Quartz; Resonators; Sensors; Surface acoustic waves; Surface chemistry; Transducers; Ultrasonics, quantum acoustics, and physical effects of sound; Various methods and equipments; Piezoelectric detector; 1/f noise; Modeling; Optimization; Resonance frequency; Quantum noise; Silicon; Microelectromechanical device; Magnetoelastic effect; Piezoelectric sensor; Magnetostriction; Measurement sensor; Crystals; Electronic nose; Bulk wave; Phonon; Chemical sensor; Quartz resonator; Surface acoustic wave resonators; Natural frequency; Plastic coating; Adsorption; Biosensor; Miniaturization; Nanotechnology
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/TUFFC.2005.1516017

Piezoelectric sensors used for the detection of chemical agents and as electronic nose instruments are based on bulk and surface acoustic wave resonators. Adsorption of gas molecules on the surface of the polymer coating is detected by a reduction of the resonance frequency of the quartz disk, subject also to fundamental quantum 1/f frequency fluctuations. The quantum 1/f limit of detection is given by the quantum 1/f formula for quartz resonators. Therefore, for quantum 1/f optimization and for calculation and improvement of the fundamental sensitivity limits, we must avoid closeness of the crystal size to the phonon coherence length, which corresponds to the maximum error and minimal sensitivity situation, as shown here. Adsorbed masses below the pg range can be detected. Microelectromechanical system (MEMS) resonators have provided a possibility for the nanominiaturization of these sensors. Essential for integrated nanotechnology, these resonant silicon bars (fingers) are excited magnetically or electrically through external applied forces, since they are not piezoelectric or magnetostrictive. The application of the quantum 1/f theory to these systems is published here for the first time. It provides simple formulas that yield much lower quantum 1/f frequency fluctuations for magnetic excitation, in comparison with electrostatically driven MEMS resonators.