scholarly journals Nanostructure-Enhanced Surface Acoustic Waves Biosensor and Its Computational Modeling

2009 ◽  
Vol 2009 ◽  
pp. 1-11 ◽  
Author(s):  
Guigen Zhang
Keyword(s):  
Acoustic Waves ◽  
High Performance ◽  
Surface Acoustic Waves ◽  
Active Surface ◽  
Underlying Mechanism ◽  
Saw Sensor ◽  
Saw Devices ◽  
Operational Capabilities ◽  
Sensing Platform ◽  
Enhanced Surface

Surface acoustic wave (SAW) devices are considered to be very promising in providing a high-performance sensing platform with wireless and remote operational capabilities. In this review, the basic principles of SAW devices and Love-mode SAW-based biosensors are discussed first to illustrate the need for surface enhancement for the active area of a SAW sensor. Then some of the recent efforts made to incorporate nanostructures into SAW sensors are summarized. After that, a computational approach to elucidate the underlying mechanism for the operations of a Love-mode SAW biosensor with nanostructured active surface is discussed. Finally, a modeling example for a Love-mode SAW sensor with skyscraper nanopillars added to in its active surface along with some selected results is presented.

Characterization of a Protein Using Saw Resonator

2014 ◽  
Vol 23 (01n02) ◽  
pp. 1420006 ◽  
Author(s):  
Jonathan Kahl ◽  
Vishal M. Dhagat ◽  
Devendra Kalonia ◽  
Faquir C. Jain
Keyword(s):  
Acoustic Wave ◽  
Surface Acoustic Wave ◽  
Acoustic Waves ◽  
High Performance ◽  
Applied Pressure ◽  
Acoustic Energy ◽  
Bulk Wave ◽  
Saw Devices ◽  
Operational Capabilities ◽  
Sensing Platform

Surface Acoustic Wave (SAW) propagation on the surface of a piezoelectric crystal is used as a carrier of information. SAW Sensors are micro-electromechanical systems (MEMS) in which high frequency acoustic waves travel close to the surface of a piezoelectric substrate. Because of confined acoustic energy near the surface within the range of one acoustic wavelength, SAW devices are highly sensitive for surface perturbation such as molecular absorption or adsorption and change of viscoelastic properties. Surface acoustic wave (SAW) devices are very promising in providing a high-performance sensing platform with wireless and remote operational capabilities. Research focus is on studying methods to characterize conductance, susceptance, viscosity, and other properties of protein samples, like albumin using SAW related resonator devices quickly and inexpensively using quantities of less than one Nano-liter. Applied pressure or bending of the quartz sets up a condition where a separation of charge occurs (due to change in dipole moment density). The potential difference is proportional to the magnitude of stress. When a mass is deposited on the electrode the resultant decrease in resonant frequency can detect mass changes at nanogram level. We propose to advance the sensitivity of the characterization by use of quartz SAW resonators since they can operate at much higher frequency than bulk wave oscillators.

WIRELESS SAW IDENTIFICATION AND SENSOR SYSTEMS

2000 ◽  
Vol 10 (04) ◽  
pp. 1143-1191 ◽  
Author(s):  
F. SCHMIDT ◽  
G. SCHOLL
Keyword(s):  
Acoustic Wave ◽  
Electromagnetic Interference ◽  
Acoustic Waves ◽  
Surface Acoustic Waves ◽  
Sensor Systems ◽  
Extreme Temperatures ◽  
Industrial Equipment ◽  
Design Rules ◽  
Saw Sensor ◽  
Saw Devices

Identification and sensor systems based on surface acoustic waves exhibit intriguing properties which have hitherto remained unexploited by semiconductor-based systems. They offer a long readout distance of up to more than 20 meters with purely passive surface acoustic wave (SAW) devices. SAW devices operate with no battery or wiring, withstand extreme temperatures and work reliably and maintenance-free over many decades even in harsh industrial environments. Because they operate at frequencies in the GHz range, SAW identification and sensor systems are well protected from the electromagnetic interference that often occurs in the vicinity of industrial equipment such as motors and high-voltage lines. The fundamentals and design rules of numerous passive wireless SAW sensor and identification systems for industrial and domestic applications as well as relevant practical work will be presented.

Characterization of RF Sputtered ZnO Piezoelectric Films Using Transmission Electron Microscope

1975 ◽  
Vol 33 ◽  
pp. 86-87
Author(s):  
Kemining W. Yeh ◽  
Richard S. Muller ◽  
Wei-Kuo Wu ◽  
Jack Washburn
Keyword(s):  
Integrated Circuit ◽  
Acoustic Waves ◽  
New Technology ◽  
Surface Acoustic Waves ◽  
Electromechanical Properties ◽  
Leading Role ◽  
Saw Devices ◽  
Transmission Electron ◽  
High Degree

Considerable and continuing interest has been shown in the thin film transducer fabrication for surface acoustic waves (SAW) in the past few years. Due to the high degree of miniaturization, compatibility with silicon integrated circuit technology, simplicity and ease of design, this new technology has played an important role in the design of new devices for communications and signal processing. Among the commonly used piezoelectric thin films, ZnO generally yields superior electromechanical properties and is expected to play a leading role in the development of SAW devices.

scholarly journals Epitaxial Growth of Sc0.09Al0.91N and Sc0.18Al0.82N Thin Films on Sapphire Substrates by Magnetron Sputtering for Surface Acoustic Waves Applications

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4630
Author(s):  
Florian Bartoli ◽  
Jérémy Streque ◽  
Jaafar Ghanbaja ◽  
Philippe Pigeat ◽  
Pascal Boulet ◽  
...  
Keyword(s):  
Acoustic Waves ◽  
Electromechanical Coupling ◽  
Surface Acoustic Waves ◽  
Electromechanical Coupling Coefficient ◽  
X Ray Diffraction ◽  
Plasma Parameters ◽  
Sapphire Substrates ◽  
Saw Devices ◽  
Transmission Electron ◽  
Electrical Characterizations

Scandium aluminum nitride (ScxAl1-xN) films are currently intensively studied for surface acoustic waves (SAW) filters and sensors applications, because of the excellent tradeoff they present between high SAW velocity, large piezoelectric properties and wide bandgap for the intermediate compositions with an Sc content between 10 and 20%. In this paper, the growth of Sc0.09Al0.91N and Sc0.18Al0.82N films on sapphire substrates by sputtering method is investigated. The plasma parameters were optimized, according to the film composition, in order to obtain highly-oriented films. X-ray diffraction rocking-curve measurements show a full width at half maximum below 1.5°. Moreover, high-resolution transmission electron microscopy investigations reveal the epitaxial nature of the growth. Electrical characterizations of the Sc0.09Al0.91N/sapphire-based SAW devices show three identified modes. Numerical investigations demonstrate that the intermediate compositions between 10 and 20% of scandium allow for the achievement of SAW devices with an electromechanical coupling coefficient up to 2%, provided the film is combined with electrodes constituted by a metal with a high density.

Modeling Development of a High-Sensitivity Escherichia coli O157:H7 Detection Based on SH SAW Sensor

2014 ◽  
Vol 925 ◽  
pp. 595-599
Author(s):  
Seng Teik Ten ◽  
Uda Hashim ◽  
Ahmad Sudin ◽  
Wei Wen Liu ◽  
Kai Loong Foo ◽  
...  
Keyword(s):  
Acoustic Waves ◽  
High Performance ◽  
Surface Acoustic Waves ◽  
Equivalent Circuit Model ◽  
High Sensitivity ◽  
Theoretical Models ◽  
Acoustic Energy ◽  
Sensitive Detection ◽  
Label Free ◽  
Element Analysis

Surface acoustic waves based devices were initially developed for the telecommunication purpose such as signal filters and resonators. The acoustic energy is strongly confined on the surface of the surface acoustic waves (SAW) based devices and consequent their ultra-sensitivity to the surface perturbation. This has made SAW permits the highly sensitive detection of utterly diminutive charges on the surface. Hence, SAW based devices have been modified to be sensors. Food contamination has become critical issue and sensitive detection devices are needed urgently as small amount of harmful bacterial pathogens such as Escherichia coli (E.coli) O157:H7with the dose fewer than 100 organisms in food products or water is enough to cause serious gastrointestinal illness to human. Therefore, ultra-high sensitive, label free biosensors have been designed in this research for the low concentration E.coli detection. After the saturated development in telecommunication filed, SAW sensors were developed for gas detections and have been moving towards biological detections recently. Shear horizontal surface acoustic wave (SHSAW), one of the SAW based types is most suitable for the liquid based application as it has the advantage of acoustic energy is not being radiated into liquid. Therefore, SHSAW device has the potential to provide high-performance sensing platform in this research. There have been a lot of complicated theoretical models for the SAW devices development since 1960 as signal filters and resonators such as from delta function model, equivalent circuit model, to the current SAW models such as coupling-of-modes (COM) model, P-matrix model and finite element analysis (FEA) model. However, SHSAW device in this research is not meant for signal filter or resonators but used for surface sensing purpose, therefore the simplicity method of the modeling is presented in the paper for the E.coli detection sensor development.

Harmonic Excitation of Surface Acoustic Waves on Gallium Nitride Thin Films for Biological and Chemical Sensor Applications

2012 ◽  
Vol 1415 ◽  
Author(s):  
J. Justice ◽  
L. E. Rodak ◽  
K. Lee ◽  
L. A. Hornak ◽  
D. Korakakis
Keyword(s):  
Thin Films ◽  
Gallium Nitride ◽  
Acoustic Waves ◽  
Chemical Sensor ◽  
Surface Acoustic Waves ◽  
Cost Effective ◽  
Harmonic Excitation ◽  
Higher Harmonics ◽  
Sensor Applications ◽  
Saw Devices

ABSTRACTGallium nitride (GaN) is a robust piezoelectric semiconductor with excellent thermal and chemical stability, making it an attractive material for surface acoustic wave (SAW) sensors operating in high temperature and harsh environments. The sensitivity of SAW devices is proportional to the square of the operating frequency. Therefore, high operating frequencies into the GHz regime are desirable for SAW sensors. For GaN, this requires sub-micron interdigital transducers (IDTs) when devices are designed to operate at the fundamental Rayleigh mode frequency. The necessity for sub-micron IDTs can increase fabrication costs and complexity. By designing SAW devices to operate at harmonic frequencies, GHz operation can be realized with relatively large IDTs, resulting in simpler and more cost effective solutions for GaN based SAW sensors. Devices have previously been designed to operate at the 5th and higher harmonics on lithium niobate, but there are no reports of using this technique on GaN in the literature. In this study, GaN thin films have been grown via metal organic vapor phase epitaxy on sapphire substrates. SAW devices designed to operate at the fundamental frequency and higher harmonics have been fabricated and measured. Operating frequencies greater than 2 GHz have been achieved using IDTs with 5 μm fingers. In addition, reduction of electromagnetic feedthrough around the 5th and 7th harmonic is demonstrated through varying ground electrode geometries.

scholarly journals Effect of Partial Ba Substitutions on the Crystallization of Sr2TiSi2O8 (STS) Glass–Ceramics and on the Generation of a SAW Signal at High Temperatures

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4648
Author(s):  
Maurice Gonon ◽  
Florian Dupla ◽  
Hassan Alhousseini ◽  
Marc Duquennoy ◽  
Nikolay Smagin ◽  
...  
Keyword(s):  
High Temperatures ◽  
Glass Ceramic ◽  
Acoustic Waves ◽  
High Stability ◽  
Surface Acoustic Waves ◽  
Glass Ceramics ◽  
Preferential Orientation ◽  
Ceramic Substrates ◽  
Saw Devices ◽  
Ba Substitution

Because of their characteristics, including a d33 of 10–15 pC/N and high stability up to temperatures over 1000 °C, polar glass–ceramics containing fresnoite crystals can be regarded as highly effective materials for applications requiring piezoelectricity at high temperatures. In the present paper we investigate barium substitutions in an Sr-fresnoite (STS) glass–ceramic. Two aspects are studied: first, the effect of the substitution on the preferential orientation of the crystallization, and second, the ability of the glass–ceramics to generate and propagate surface acoustic waves (SAW) at high temperatures. XRD analyses show that a 10 at.% substitution of Ba allows us to keep a strong preferential orientation of the (00l) planes of the fresnoite crystals down to more than 1 mm below the surfaces. Higher substitution levels (25 and 50 at.%), induce a non-oriented volume crystallization mechanism that competes with the surface mechanism. SAW devices were fabricated from glass–ceramic substrates with 0, 10 and 25 at.% Ba substitutions. Temperature testing reveals the high stability of the frequency and delay for all of these devices. The glass–ceramic with a 10 at.% Ba substitution gives the strongest amplitude of the SAW signal. This is attributed to the high (00l) preferential orientation and the absence of disoriented volume crystallization.

Analysis of Surface Acoustic Waves in Layered Piezoelectric Media and its Applications to the Design of Saw Devices

2003 ◽  
Vol 19 (1) ◽  
pp. 225-232 ◽  
Author(s):  
T.-T. Wu ◽  
Y.-Y. Chen
Keyword(s):  
Acoustic Waves ◽  
Velocity Dispersion ◽  
Metal Layer ◽  
Effective Permittivity ◽  
Surface Acoustic Waves ◽  
Frequency Bandwidth ◽  
Piezoelectric Media ◽  
Saw Devices ◽  
Phase Velocity Dispersion

ABSTRACTIn this paper, we utilized a Stroh based formulation for solving problems of surface waves in layered piezoelectric media, and then, applied it to analyze surface acoustic wave (SAW) devices. The determination of the optimal cut of a piezoelectric crystal and the choice of the best propagation of SAW devices were given. The dispersion induced by a thin metal layer on SAW propagation in a SAW device was analyzed and discussed. Finally, we applied the formulation to calculate the effective permittivity and phase velocity dispersion of a LiNbO3/Diamond layered SAW device. Both of the null frequency bandwidth and the insertion loss of the dispersive SAW device were obtained.

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