Abstract
Introduction: In this paper, a surface acoustic wave sensor (SAW) for dangerous gas sensing applications has been designed and validated. The glucose sensor applications have been simulated to show that the piezoelectric material has a high significance for use in detection.
Background: Detection of gases is one of the major applications. SAW gas sensors extend their services into medical and even in power plants. A Surface Acoustic Wave (SAW) is an acoustic wave that propagates on the surface of an elastic material (usually a solid), with an amplitude that decreases with the depth of the substrate.
Objectives: SAW devices typically use electrodes on a piezoelectric material to convert an electrical signal to a SAW.
Methods: This paper aimed to review the significance of piezoelectric materials and focused on MEMS-based SAW. The resonance frequencies of a SAW gas sensor, consisting of an Interdigital Transducer (IDT) etched onto a piezoelectric substrate and covered with a thin Poly Isobutylene (PIB) film, were investigated.
Results: The mass of the PIB film increases as PIB selectivity adsorbs CH2Cl2 (Dichloromethane, DCM) in the air. This causes a shift in resonance to a slightly lower frequency.
Conclusion: Our characterization of the piezoelectric material has shown a high significance when a sensitive layer of gas is etched for detecting the dangerous gases; we used it in another application of glucose sensor to show the importance of our system. The sensor of the glucose sensor application has been designed and simulated by a finite element analysis, which was conducted on LiNbO3 pellets. This model was applied to verify the sensing properties of DCM and glucose. On the other hand, the glucose sensor and the toxic gas detection allowed us to measure the concentration, whether it is for the dangerous gases or glucose. The concentration of external glucose and the current density versus glucose concentration were measured by a finite element.
Keywords: MEMS, interdigital transducer (IDT), surface acoustic wave (SAW), sensor, piezoelectric material, numerical simulation.
Graphical Abstract
[http://dx.doi.org/10.1016/j.mee.2018.07.016]
[http://dx.doi.org/10.1016/j.sna.2018.05.044]
[http://dx.doi.org/10.1016/j.snb.2015.11.045]
[http://dx.doi.org/10.1016/j.mspro.2014.07.190]
[http://dx.doi.org/10.1016/j.snb.2014.08.010]
[http://dx.doi.org/10.1016/j.ultras.2017.09.018] [PMID: 28988142]
[http://dx.doi.org/10.1016/j.snb.2017.04.032]
[http://dx.doi.org/10.1016/j.protcy.2017.04.089]
[http://dx.doi.org/10.1016/j.apacoust.2017.05.008]
[http://dx.doi.org/10.1016/j.diamond.2016.03.016]
[http://dx.doi.org/10.1016/j.firesaf.2017.04.029]
[http://dx.doi.org/10.1016/j.jngse.2018.07.012]
[http://dx.doi.org/10.1016/B978-1-895198-92-8.50135-X]
[http://dx.doi.org/10.1016/j.sna.2018.03.002]
[http://dx.doi.org/10.1016/j.mtcomm.2018.09.024]
[http://dx.doi.org/10.1016/j.trac.2017.04.003]
[http://dx.doi.org/10.1088/2043-6262/7/2/025002]
[http://dx.doi.org/10.1016/j.ijggc.2018.07.026]
[http://dx.doi.org/10.1166/sl.2017.3868]
[http://dx.doi.org/10.1051/epjap/2019190085]
[http://dx.doi.org/10.1088/1757-899X/186/1/012028]
[http://dx.doi.org/10.1088/1757-899X/353/1/012013]