Modeling and Characterization of Pre-Charged Collapse-Mode CMUTs

Recently, the applications of ultrasound transducers expanded from high-end diagnostic tools to point of care diagnostic devices and wireless power receivers for implantable devices. These new applications additionally require that the transducer technology must comply to biocompatibility and manufacturing scalability. In this respect,...

Ultrasound Tracking and Data Telemetry using CMUTs

Implantable Medical Devices (IMDs) offer a wide range of applications including but not limited to blood pressure monitoring, bladder pressure sensing, glucose level monitoring, neurostimulation etc. For such applications, it is often desired that an IMD is as small as possible while meeting the required objective. Consequently, using a battery...

Bulk Acoustic Wave Based Mocrfluidic Particle Sorting with Capacitive Micromachined Ultrasonic Transducers

The main limitation of acoustic particle separation for microfluidic application is its low sorting efficiency. This is due to the weak coupling of surface acoustic waves (SAWs) into the microchannel. In this work, we demonstrate bulk acoustic wave (BAW) particle sorting using capacitive micromachined ultrasonic transducers (CMUTs) for the first...

Time-efficient low power time/phase-reversal beamforming for the tracking of ultrasound implantable devices

Ultrasound (US) has recently gained attention for powering and communication with implantable devices due to its short wavelength and low attenuation. However, beam mis-alignments cause a sharp decrease in the amount of transferred power and quality of communication. This work investigates a telemetry protocol that relies on the difference in...

The long-term reliability of pre-charged CMUTs for the powering of deep implanted devices

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...

A microwatt telemetry protocol for targeting deep implants

Implantable medical devices are becoming smaller and more deeply implanted in the human body for various applications (i.e., neurostimulation, drug delivery, bone fracture monitoring). Therefore, an efficient ultrasound power transfer link is needed to charge these devices. However, this is challenging because each ultrasound transducer has...

Real-Time Coded Excitation Imaging Using a CMUT-based Side Looking Array for Intravascular Ultrasound

Intravascular ultrasound (IVUS) is a well-established diagnostic method that provides images of the vessel wall and atherosclerotic plaques. We investigate the potential for phased-array IVUS utilizing coded excitation (CE) for improving the penetration depth and image signal-to-noise ratio (SNR). It is realized on a new experimental...

Pre-charged collapse-mode capacitive micromachined ultrasonic transducer (CMUT) for broadband ultrasound power transfer

Using ultrasound to power deeply implanted biomedical devices is a promising technique due to its low attenuation in body tissue and its short wavelength that allows precise focusing of the energy. Ultrasound energy harvesting conventionally has been done using lead zirconate titanate (PZT) ultrasound transducers, which uses the piezoelectric...

Ultrasound Energy Transfer using Charged CMUTs

Implantable medical devices (IMDs) such as cardiac pacemakers, cochlear implants, and neurostimulators improve millions of people’s lives every day. Over the years, IMDs have significantly improved in function, increased in lifetime, and decreased in size. However, further miniaturisation is limited by the batteries used to power these devices,...

Towards CMUT for Neurostimulation: The Development of an Experimental Model for the Validation of Ultrasound Neuromodulation and Back-side Vent Etching for Low-Frequency CMUT Devices

Ultrasound (US) neurostimulation, the non-pharmacological, reversible excitation or inhibition of the nervous system using ultrasonic waves, is emerging as a high interest topic in neurostimulation research. In the current project, an attempt was made to demonstrate US neuromodulation in a Lumbricus Terrestris model of evoked compound action...

3D Robotic Ultrasound System: A 3D Volumetric Ultrasound Imaging System using a CMUT Phased Array and a Robotic Arm

Diagnostic imaging is a fundamental requirement for the effective treatment of about 25 % of patients globally. Ultrasound imaging is considered the safest, least expensive and most convenient diagnostic imaging modality. Its widespread adoption has been in the area of 2D imaging. However, the accuracy of diagnosis with 2D ultrasound imaging is...

An Efficacious and Safe Multichannel Neurostimulator Powered by an Ultrasonic Wireless Link

Neurostimulation is a common medical treatment modality used to treat neurological disorders. It applies electrical pulses to revert and prevent undesired neural behavior or to create desired neural behavior. The required specificity of said stimulation treatments is oftentimes achieved by implanting the neurostimulator close to the target area....

MEMS ultrasound for active implantable devices

During the past decade, Implantable biomedical devices have emerged as an efficient treatment for neurological disorders. Among them, low-intensity focused ultrasound (LIFU) has recently gained interest due to its focusing ability, depth of penetration and reversible effects. Although the exact biophysical mechanism that leads to the interaction...

Acoustically Induced Microenvironments: Building blocks for organ models in-vitro

The goals of this graduation project are to introduce and prove the concept of an Acoustically Induced Microenvironment (AIM), and feature the application of Capacitive Micro machined Ultrasonic Transducers (CMUTs) in microfluidics. AIMs are conceived as a series of building blocks for more complex systems where the driving technology is...

Miniaturized Optical Data Link Assembly for 360 um Guidewires

We propose a novel concept for a high-speed optical data link in Ø 360 µm cardiovascular interventional imaging guidewires. The concept is based on the recently introduced Flex-to-Rigid (F2R) technology platform. This technology allows for smaller intravascular imaging devices with a more compact form-factor. We extended the existing F2R...