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Abstract In recent years, there has been an increased interest in continuous monitoring of patients and their Implanted Medical Devices (IMDs) with different wireless technologies such as ultrasounds. This paper demonstrates a high data-rate intrabody communication link based on Lithium Niobate (LN) Piezoelectric Micromachined Ultrasonic Transducers (pMUTs). The properties of the LN allow to activate multiple flexural mode of vibration with only top electrodes. When operating in materials like the human tissue, these modes are merging and forming a large communication bandwidth. Such large bandwidth, up to 400 kHz, allows for a high-data rate communication link for IMDs. Here we demonstrate a full communication link in a tissue phantom with a fabricated LN pMUT array of 225 elements with an area of just 3 by 3 mm square, showing data-rates up to 800 kbits/s, starting from 3.5 cm and going up to 13.5 cm, which covers the vast majority of IMDs.
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Characterization of Curved Piezoelectric Micromachined Ultrasound Transducers Fabricated by Chip-Scale Glass Blowing Technique
Ultrasound has been extensively used and investigated in medical applications, such as medical imaging [1] and drug delivery [2], because of advantages such as noninvasiveness, good penetration, good sensitivity, and ease of use. Prior to the development of piezoelectric micromachined ultrasound transducers (pMUTs), conventional transducers were made of piezoelectric ceramics, such as lead zirconate titanate [3]. These materials when operated in thickness mode exhibit a large impedance mismatch between the transducer surface and medium resulting in lower bandwidth unless augmented with one or more matching layers. With the development of MEMS technology, improvements in MUTs have been realized in several aspects, such as wide bandwidth without the addition of matching layers [4], smaller cell size, therefore higher operating frequency and better resolution, and easier fabrication of large arrays at lower cost [5]. Despite lower electromechanical coupling coefficient, the low-power consumption feature makes pMUTs good candidates for a variety of applications, including intrabody communication [6] and fingerprint sensing [7].
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- Award ID(s):
- 2053277
- PAR ID:
- 10531815
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Sensors Letters
- Volume:
- 7
- Issue:
- 10
- ISSN:
- 2475-1472
- Page Range / eLocation ID:
- 1 to 4
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/LSENS.2023.3308112
