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Title: Relationship Between Lateral Field Excited AT-Cut Quartz Crystal Microbalance Operation and Acoustic Plate Modes
The operational modes of lateral field excited (LFE) quartz crystal microbalances (QCMs) under various electrical boundary conditions have been under investigation for use in sensing applications. The present results indicate connections between the behaviors of acoustic plate modes (APMs) and LFE-QCM modes. The influences of deposited thin conducting and semiconducting films on the mode responses of LFE-QCMs strongly agree with reported effects on APMs. Thus the main operating modes of LFE devices are concluded to be laterally varying APMs, which may be close in character to thickness modes. Mode response changes caused by slowly varying surface curvature are explained from this perspective. The consistency of the usual LFE thickness mode coupling formalism is evaluated, and the superposition of partial waves method is found to be more appropriate for analyzing LFE devices. This view of LFE devices operating through APMs supports improved sensing applications and investigations through access to existing APM knowledge.
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Proceedings of the 2020 IEEE International Ultrasonics Symposium (IUS)
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1 to 4
Sponsoring Org:
National Science Foundation
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