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Interdigitated transducer devices provide an advantageous platform to study stress-enhanced interfacial phenomena at elevated temperatures but require a thorough understanding of temperature-dependent material properties. In this study, the temperature dependence of the piezoelectric coefficient for gallium arsenide is determined from 22 ℃ to 177 ℃. Experimental scattering parameter responses are measured for a two-port surface acoustic wave resonator at different temperatures and piezoelectric coefficient values are extracted using a frequency-domain finite element method simulation. Device measurements are taken using an interdigitated transducer fabricated on semi-insulating GaAs(100), oriented in the 〈110〉 direction and device resonant frequencies are shown to decrease with increasing temperature. The experimental scattering response is used to reconcile the simulated scattering response and extract the 𝑒14 piezoelectric coefficient, which is shown to increase linearly with temperature. Using the extracted 𝑒14, surface acoustic wave analysis is completed to study the magnitude of bulk stress values and surface displacement over the experimental temperature range produced by a standing surface acoustic wave field. Surface displacement measurements are taken at room temperature using contact-mode AFM, which corroborate the simulation predictions. The modeling results demonstrate an interdigitated transducers potential as an experimental stage to study surface and bulk stress effects on temperature-sensitive phenomena.
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Exploring electromechanical utility of GaAs interdigitated transducers; using finite-element-method-based parametric analysis and experimental comparison
Analysis of interdigitated transducers often relies on phenomenological models to approximate device electrical performance. While these approaches prove essential for signal processing applications, phenomenological models provide limited information on the device’s mechanical response and physical characteristics of the generated acoustic field. Finite element method modeling, in comparison, offers a robust platform to study the effects of the full device geometry on critical performance parameters of interdigitated transducer devices. In this study, we fabricate a surface acoustic wave resonator on semi-insulating GaAs [Formula: see text], which consists of an interdigitated transducer and acoustic mirror assembly. The device is subsequently modeled using fem software. A vector network analyzer is used to measure the experimental device scattering response, which compares well with the simulated results. The wave characteristics of the experimental device are measured by contact-mode atomic force microscopy, which validates the simulation’s mechanical response predictions. We further show that a computational parametric analysis can be used to optimize device designs for series resonance frequency, effective coupling coefficient, quality factor, and maximum acoustic surface displacement.
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- PAR ID:
- 10393914
- Date Published:
- Journal Name:
- Journal of Vacuum Science & Technology B
- Volume:
- 41
- Issue:
- 1
- ISSN:
- 2166-2746
- Page Range / eLocation ID:
- 013203
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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null (Ed.)Interdigitated transducer devices provide an advantageous platform to study stress-enhanced interfacial phenomena at elevated temperatures but require a thorough understanding of temperature-dependent material properties. In this study, the temperature dependence of the piezoelectric coefficient for gallium arsenide is determined from 22 ℃ to 177 ℃. Experimental scattering parameter responses are measured for a two-port surface acoustic wave resonator at different temperatures and piezoelectric coefficient values are extracted using a frequency-domain finite element method simulation. Device measurements are taken using an interdigitated transducer fabricated on semi-insulating GaAs(100), oriented in the 〈110〉 direction and device resonant frequencies are shown to decrease with increasing temperature. The experimental scattering response is used to reconcile the simulated scattering response and extract the e_14 piezoelectric coefficient, which is shown to increase linearly with temperature. Using the extracted e_14, surface acoustic wave analysis is completed to study the magnitude of bulk stress values and surface displacement over the experimental temperature range produced by a standing surface acoustic wave field. Surface displacement measurements are taken at room temperature using contact-mode AFM, which corroborate the simulation predictions. The modeling results demonstrate an interdigitated transducers potential as an experimental stage to study surface and bulk stress effects on temperature-sensitive phenomena.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1116/6.0002169
