TY - GEN
T1 - The long-term reliability of pre-charged CMUTs for the powering of deep implanted devices
AU - Saccher, Marta
AU - Kawasaki, Shinnosuke
AU - Dekker, Ronald
N1 - Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care
Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.
PY - 2021
Y1 - 2021
N2 - Recently, focused ultrasound has been proposed to power deeply implanted medical devices. Almost exclusively, lead zirconate titanate (PZT) transducers are used to convert acoustic energy into electrical energy. Unfortunately, these lead containing devices cannot be hermetically encapsulated since that would block the ultrasound. We propose the use of biocompatible Capacitive Micromachined Ultrasonic Transducer (CMUT) elements to replace traditional PZT transducers. In addition, to eliminate the external bias voltage, we introduced a charge trapping Al2O3 layer inside the CMUT to create a built-in bias voltage. These devices can be pre-charged and used as a receiver for US power. In this work, the viability of charged CMUTs to power deep implants was explored by investigating the effect of the charging parameters and by performing Accelerated Lifetime Tests (ALT). The estimated lifetime at body temperature ranges between 2.5 to 3.5 years at body temperature, which significantly depends on the charging parameters.
AB - Recently, focused ultrasound has been proposed to power deeply implanted medical devices. Almost exclusively, lead zirconate titanate (PZT) transducers are used to convert acoustic energy into electrical energy. Unfortunately, these lead containing devices cannot be hermetically encapsulated since that would block the ultrasound. We propose the use of biocompatible Capacitive Micromachined Ultrasonic Transducer (CMUT) elements to replace traditional PZT transducers. In addition, to eliminate the external bias voltage, we introduced a charge trapping Al2O3 layer inside the CMUT to create a built-in bias voltage. These devices can be pre-charged and used as a receiver for US power. In this work, the viability of charged CMUTs to power deep implants was explored by investigating the effect of the charging parameters and by performing Accelerated Lifetime Tests (ALT). The estimated lifetime at body temperature ranges between 2.5 to 3.5 years at body temperature, which significantly depends on the charging parameters.
KW - capacitive micromachined ultrasound transducers
KW - pre-charged CMUT
KW - zero-bias transducers
KW - ultrasound power transfer
KW - accelerated lifetime test
UR - http://www.scopus.com/inward/record.url?scp=85122892794&partnerID=8YFLogxK
U2 - 10.1109/IUS52206.2021.9593683
DO - 10.1109/IUS52206.2021.9593683
M3 - Conference contribution
SN - 978-1-6654-4777-5
T3 - IEEE International Ultrasonics Symposium, IUS
SP - 1
EP - 4
BT - 2021 IEEE International Ultrasonics Symposium (IUS)
PB - IEEE
CY - Piscataway
T2 - 2021 IEEE International Ultrasonics Symposium (IUS)
Y2 - 11 September 2021 through 16 September 2021
ER -