Skin-Conformal PMN-PT Ultrasonic Sensor for Cuffless Blood Pressure Sensing via Eutectic Solder Integration

Skin-Conformal PMN-PT Ultrasonic Sensor for Cuffless Blood Pressure Sensing via Eutectic Solder Integration | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Skin-Conformal PMN-PT Ultrasonic Sensor for Cuffless Blood Pressure Sensing via Eutectic Solder Integration Shin Hur, Syed Turab Haider Zaidi, Dong Hun Kim, Muhammad Ali Shah, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7267229/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 01 Jan, 2026 Read the published version in Microsystems & Nanoengineering → Version 1 posted 9 You are reading this latest preprint version Abstract Wearable ultrasonic systems are emerging as promising tools for noninvasive cardiovascular monitoring, enabling the real-time assessment of vascular dynamics without the need for cuff-based measurements. However, the integration of high-performance piezoelectric materials into flexible skin-conformal arrays poses challenges in terms of mechanical durability, acoustic fidelity, and scalability. In this study, we present a flexible 5×4 ultrasonic transducer array (UTA) based on Lead magnesium niobate-lead Titanate (PMN-PT 1–3) composite elements for continuous blood pressure monitoring. To achieve reliable integration, we employed a dual-sided eutectic solder bonding method using an SnBi alloy to ensure low-temperature attachment without depolarization. The fabricated UTA operates at a center frequency of 6.0 MHz with an acceptance angle of 45°, enabling robust signal acquisition under varying angular conditions. Time-of-flight simulations and in vitro testing of vascular phantoms demonstrated the accurate tracking of vessel diameters and the estimation of real-time blood pressure. The UTA achieved systolic and diastolic pressure measurements within 4 mmHg of those of a commercial reference sensor. These results highlight the feasibility of scalable and flexible ultrasound systems for wearable hemodynamic sensors, suggesting their potential for next-generation point-of-care diagnostics. Physical sciences/Engineering Physical sciences/Materials science Flexible ultrasonic transducer array PMN-PT 1–3 composite Noninvasive blood pressure monitoring Eutectic solder bonding Vascular phantom Full Text Additional Declarations There is no conflict of interest Supplementary Files SupplemDraft6BCLee.docx Skin-Conformal PMN-PT Ultrasonic Sensor for Cuffless Blood Pressure Sensing via Eutectic Solder Integration Cite Share Download PDF Status: Published Journal Publication published 01 Jan, 2026 Read the published version in Microsystems & Nanoengineering → Version 1 posted Editorial decision: revise 03 Sep, 2025 Review # 2 received at journal 21 Aug, 2025 Review # 1 received at journal 20 Aug, 2025 Reviewer # 2 agreed at journal 11 Aug, 2025 Reviewer # 1 agreed at journal 10 Aug, 2025 Reviewers invited by journal 10 Aug, 2025 Submission checks completed at journal 04 Aug, 2025 Editor assigned by journal 01 Aug, 2025 First submitted to journal 01 Aug, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7267229","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":498428117,"identity":"8462e821-e599-4d43-8227-639bb5852d43","order_by":0,"name":"Shin 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However, the integration of high-performance piezoelectric materials into flexible skin-conformal arrays poses challenges in terms of mechanical durability, acoustic fidelity, and scalability. In this study, we present a flexible 5\u0026times;4 ultrasonic transducer array (UTA) based on Lead magnesium niobate-lead Titanate (PMN-PT 1\u0026ndash;3) composite elements for continuous blood pressure monitoring. To achieve reliable integration, we employed a dual-sided eutectic solder bonding method using an SnBi alloy to ensure low-temperature attachment without depolarization. The fabricated UTA operates at a center frequency of 6.0 MHz with an acceptance angle of 45\u0026deg;, enabling robust signal acquisition under varying angular conditions. Time-of-flight simulations and in vitro testing of vascular phantoms demonstrated the accurate tracking of vessel diameters and the estimation of real-time blood pressure. 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