Optimization of interdigital transducers for the generation of surface acoustic waves over a large bandwidth (20–125 MHz)

Fall, Dame; Duquennoy, Marc; Ouaftouh, Mohammadi; Smagin, Nikolay; Piwakowski, Bogdan; Jenot, Frédéric

doi:10.1016/j.sna.2018.03.002

Cited by 17 publications

(10 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The varied frequency setup enables the wave modes and the reflectivity to be controlled and for the pitch of the wave to be linearly modulated. This type of design can possess a huge number of bandwidths [ 2 , 90 , 153 ]. Figure 15 shows an example of a dispersive delay line configuration.…”

Section: Configuration Of the Interdigitated Electrodes In The Saw De...mentioning

confidence: 99%

Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications

Mandal

Banerjee

2022

Sensors

211

100

View full text Add to dashboard Cite

Surface acoustic waves (SAWs) are the guided waves that propagate along the top surface of a material with wave vectors orthogonal to the normal direction to the surface. Based on these waves, SAW sensors are conceptualized by employing piezoelectric crystals where the guided elastodynamic waves are generated through an electromechanical coupling. Electromechanical coupling in both active and passive modes is achieved by integrating interdigitated electrode transducers (IDT) with the piezoelectric crystals. Innovative meta-designs of the periodic IDTs define the functionality and application of SAW sensors. This review article presents the physics of guided surface acoustic waves and the piezoelectric materials used for designing SAW sensors. Then, how the piezoelectric materials and cuts could alter the functionality of the sensors is explained. The article summarizes a few key configurations of the electrodes and respective guidelines for generating different guided wave patterns such that new applications can be foreseen. Finally, the article explores the applications of SAW sensors and their progress in the fields of biomedical, microfluidics, chemical, and mechano-biological applications along with their crucial roles and potential plans for improvements in the long-term future in the field of science and technology.

show abstract

Section: Configuration Of the Interdigitated Electrodes In The Saw De...mentioning

confidence: 99%

Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications

Mandal

Banerjee

2022

Sensors

211

100

View full text Add to dashboard Cite

show abstract

“…The broadband surface acoustic waves emitter used in this study is based on an interdigital transducer formed of interdigitated chirp electrodes deposited on 128° Y-cut LiNbO 3 . Interdigital transducers consist of comb-shaped metal electrodes (often made of gold or aluminum) composed of interlocking fingers with a finger overlap distance of W [ 20 , 21 , 22 ]. The IDT electrode structure is presented at the top of Figure 1 a for an IDT with a constant electrode period.…”

Section: Broadband (100–240 Mhz) Surface Acoustic Waves Emittermentioning

confidence: 99%

Development of a Broadband (100–240 MHz) Surface Acoustic Wave Emitter Devoted to the Non-Destructive Characterization of Sub-Micrometric Thin Films

Duquennoy

Smagin

Kadi

et al. 2022

Sensors

Self Cite

View full text Add to dashboard Cite

In the ultrasonic non-destructive evaluation of thin films, it is essential to have ultrasonic transducers that are able to generate surface acoustic waves (SAW) of suitably high frequencies in a wide frequency range of between ten and several hundred megahertz. If the characterization is carried out with the transducer in contact with the sample, it is also necessary that the transducers provide a high level of mechanical displacement (>100 s pm). This level allows the wave to cross the transducer–sample interface and propagate over the distance of a few millimeters on the sample and be properly detected. In this paper, an emitter transducer formed of interdigitated chirp electrodes deposited on 128° Y-cut LiNbO3 is proposed. It is shown that this solution efficiently enables the generation of SAW (displacement level up to 1 nm) in a frequency range of between 100 and 240 MHz. The electrical characterization and a displacement field analysis of SAW by laser Doppler vibrometry are presented. The transducer’s significant unidirectionality is demonstrated. Finally, the characterization of two titanium thin films deposited on silicon is presented as an example. A meaningful SAW velocity dispersion (~10 m/s) is obtained, which allows for the precise estimation (5% of relative error) of the submicrometer thickness of the layers (20 and 50 nm).

show abstract

“…The configuration was optimized in order to overcome high frequency attenuation of high frequency SAW. 33 The IDT active zone length was equal to 4 mm.…”

Section: A Interdigital Transducers For Generating Surface Acoustic W...mentioning

confidence: 99%

“…The difference in excitation and response signal spectra is due to the particularities of the IDT transfer function optimized for high frequency emissions. 33 In Fig. 7(a), all the spectra (in red) and their average (in black) are plotted.…”

Section: Chirp Excitationmentioning

confidence: 99%

Non-destructive characterization of surfaces and thin coatings using a large-bandwidth interdigital transducer

Fall

Duquennoy

Ouaftouh

et al. 2018

Review of Scientific Instruments

Self Cite

View full text Add to dashboard Cite

This paper deals with non-destructive testing of thin layer structures using Rayleigh-type waves over a broad frequency range . The dispersion phenomenon was used to characterize a layeron-substrate-type sample comprising a thin layer of platinum 100 nm thick on a silicon substrate. The originality of this paper lies in the investigation of different ways of generating surface acoustic waves (SAWs) with large bandwidth interdigital transducers (IDTs) as well as the development of a measuring device to accurately estimate the SAW phase velocity. In particular, this study focuses on comparing the performance (in terms of SAW amplitude and bandwidth) of different excitations imposed on IDTs. The three types of excitations are burst, impulse, and chirp. The interest of chirp excitation compared to the other two types was clearly demonstrated in terms of the SAW bandwidth and amplitude of displacement. With these IDT transducers, measurements could be performed over a wide frequency band (20-125 MHz), and consequently, dispersion curves could be obtained over a wide frequency band with a range of velocity variations in the order of 100 m/s. Under these conditions, an extremely accurate estimate of the phase velocity as a function of the frequency could be obtained using a Slant Stack transformation. Finally, from these experimental dispersion curves and theoretical dispersion curves, an accurate estimate of the thickness of the layer could be obtained by inversion. This estimated thickness was then confirmed using profilometer measurements.

show abstract

Optimization of interdigital transducers for the generation of surface acoustic waves over a large bandwidth (20–125 MHz)

Cited by 17 publications

References 21 publications

Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications

Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications

Development of a Broadband (100–240 MHz) Surface Acoustic Wave Emitter Devoted to the Non-Destructive Characterization of Sub-Micrometric Thin Films

Non-destructive characterization of surfaces and thin coatings using a large-bandwidth interdigital transducer

Contact Info

Product

Resources

About

Optimization of interdigital transducers for the generation of surface acoustic waves over a large bandwidth (20–125 MHz)

Cited by 17 publications

References 21 publications

Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications

Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications

Development of a Broadband (100–240 MHz) Surface Acoustic Wave Emitter Devoted to the Non-Destructive Characterization of Sub-Micrometric Thin Films

Non-destructive characterization of surfaces and thin coatings using a large-bandwidth interdigital transducer

Contact Info

Product

Resources

About

Optimization of interdigital transducers for the generation of surface acoustic waves over a large bandwidth (20–125 MHz)