/PMUT array design for multi-frequency medical imaging

PMUT array design for multi-frequency medical imaging

Research & development - Leuven | More than two weeks ago

Design the next-generation ultrasound imaging probe

Thanks to its non-invasiveness and bed-side portability, medical ultrasound imaging is well established in clinical practices. However, most commercial ultrasound transducers currently use one central frequency, inevitably linking it to a fixed resolution and penetration depth. A multi-frequency ultrasound transducer could enable emerging applications such as multi-scale imaging and harmonic contrast agent imaging.

The MEMS team of Imec Leuven is developing Piezoelectric Micromachined Ultrasound Transducers for a multitude of ultrasound applications. Currently, classical ultrasound transducer consist of a thick layer of piezo material, sandwiched between two electrodes. Their miniaturized counterparts (PMUTs) allow for a much smaller form factor, easier integration with supporting electronics and smart design that allows multiple operating frequencies in one transducer probe. In this master thesis topic, the goal is to optimize the PMUT for multi-frequency behavior.

PMUTs are miniaturized drums containing a piezoelectric layer in a membrane that can generate and pick-up mechanical deformation of the suspended membrane. This allows PMUTs to emit and receive ultrasound waves by respectively vibrating the membrane or detecting the deformation of the membrane by an incoming wave (see sketch below)

Fig 1: Sketch of PMUT cross-section and working principle.

The aim of this master thesis is to design and characterize a new generation of multi-frequency PMUT arrays, comparing it to state-of-the-art technology.  The research work includes, but is not limited to: 1) design and numerical simulation of PMUT devices and PMUT arrays; 2) acoustic and electronic characterization of PMUT devices; 3) benchmarking with state of the art technology. The work is estimated to be: 60% simulations/design,  40% characterization. Generally, this is a topic for a student who is eager to understand MEMS devices design and characterization, together with ultrasound imaging.

Type of project: Internship, Thesis, Combination of internship and thesis

Duration: 6 months - 1 year

Required degree: Master of Engineering Technology, Master of Science, Master of Engineering Science

Required background: Physics, Nanoscience & Nanotechnology, Mechanical Engineering, Electromechanical engineering, Materials Engineering

Supervising scientist(s): For further information or for application, please contact: Marcus Ingram (Marcus.Ingram@imec.be) and Margo Billen (Margo.Billen@imec.be) and Veronique Rochus (Veronique.Rochus@imec.be)

Only for self-supporting students.