Wearable ultrasound devices are actively used in various medical settings, including hospital diagnostics, rehabilitation monitoring, and telemedicine. However, most commercial devices currently rely on lead (Pb)-based piezoelectric ceramics, which are harmful to the human body and the environment, making it difficult to ensure both performance and safety. This has increased the demand for new ultrasound transducer technologies that can completely replace lead while achieving high performance.
The research team led by Dr. Byung Chul Lee at the Bionics Research Center of the Korea Institute of Science and Technology (KIST, President Sang-Rok Oh), in collaboration with Prof. Jae-Woong Jeong at KAIST (President Kwang-Hyung Lee), Prof. Whal Lee at Seoul National University Hospital (Director Young-Tae Kim), and Prof. Pierre T. Khuri-Yakub at Stanford University (President Jonathan Levin), announced the development of a silicon-based disposable eco-friendly ultrasound patch. This achievement marks the first realization of superior performance beyond conventional high-cost lead-based ultrasound transducers without using lead at all.
The team fabricated an ultrathin patch only a few hundred micrometers thick by precisely processing silicon into a nanocolumn structure using semiconductor technology. By eliminating the matching and backing layers—components considered essential in conventional ultrasound transducers—they succeeded in maintaining stable performance while achieving a flexible and thin structure. As a result, the new device delivers improved output and image quality while completely removing lead.
The patch's performance and applicability were verified in actual experiments. Compared to commercial transducers, it demonstrated over 30% higher output pressure, producing significantly improved image quality. It was also able to reliably measure blood flow velocity and vessel diameter in highly mobile areas such as the neck. In addition, it achieved over 96% accuracy compared to clinical blood pressure monitors, confirming its potential for medical applications. The technology is expected to be widely used in telemedicine and personalized healthcare devices.
Since the silicon-based ultrasound transducer is fabricated using semiconductor processes, it enables low-cost, large-scale production and imposes less environmental burden after use. In particular, its production cost is estimated at about 1/20 that of conventional lead-based devices, making it highly economical and environmentally friendly. The team expects it will lead the market for disposable ultrasound patches. They plan to further validate its safety and reliability in diverse clinical environments and expand its applications to various medical fields, including early diagnosis of cardiovascular diseases, rehabilitation monitoring, and mental health management.
Dr. Byung Chul Lee at KIST stated, "This research is highly meaningful in that we successfully developed an ultrasound patch that anyone can use safely by replacing harmful lead with silicon."
Prof. Whal Lee at Seoul National University Hospital commented, "Compared to piezoelectric transducer-based devices, silicon-based ultrasound devices are flexible and can be manufactured in diverse forms, significantly broadening the range of medical applications for ultrasound imaging."
