PhD - Leuven | More than two weeks ago
Parametric array effect, based on nonlinear behavior of wave propagation medium, has been subject of numerous theoretical and experimental studies since the 1960s. By beneficially exploiting this phenomenon, a highly directional low frequency loudspeakers can be built. In such systems resultant audible sound beam (secondary wave) can be indirectly generated with a set of relatively small transducers emitting ultrasonic signals (primary waves).
Since decades, imec is leading the development of novel MEMS technologies such piezoelectric and capacitive MEMS ultrasound transducers based on CMOS-compatible Silicon technology. Due to the increasing interest in producing large arrays of such sensors, imec recently developed innovative polymer ultrasound transducers using the Large Area Electronics (LAE) thin-film technology platform which allows to produce passive and active components in thin-film frameworks with world-leading performance and in flexible form factors.
The purpose of this PhD is first to design a directional loudspeaker composed of an array of ultrasound transducers capable to generate high acoustic power and narrow low-frequency sound beam. This task will consist of modelling the nonlinear behavior of acoustics at high intensity as well as improving the transmit performance of the transducer itself. Working in close collaboration with the process team, the candidate will propose designs to improve acoustic performance. The second part of the work will be to characterize the pMUT mechanically and acoustically to validate the acoustic and pMUT models. Finally, the last step is to realize a demonstrator to evaluate the final performance of the loudspeaker. The PhD student will conduct the research over the entire cycle in the imec laboratories: 1) design and numerical modelling of pMUT parametric array; 2) collaboration with the process team; 3) acoustical and mechanical characterization; 4) realization and characterization of the loudspeaker.
You are a highly motivated student, with background in nano-engineering, physics, material science, electrical engineering, or related. You have an interest in the designing ultrasound transducer, in nonlinear acoustics and in characterization of acoustical performance of developed devices. It is expected that you will present results regularly. You are a team player and have good communication skills as you will work in a multidisciplinary and multicultural team spanning several imec departments. Given the international character of imec, an excellent knowledge of English is a must.
Required background: nano-engineering, physics, materials science or electrical engineering with strong affinity for device physics
Type of work: 15% literature study, 30% modeling, 20% design, 35% characterization
Supervisor: Paul Heremans
Co-supervisor: Xavier Rottenberg
Daily advisor: Veronique Rochus, Alexey Podkovskiy
The reference code for this position is 2021-108. Mention this reference code on your application form.