Fully implantable self-powered hearing aids, with no external unit, could significantly increase the life quality of patients suffering severe hearing loss. This highly demanding concept, however, requires a strongly miniaturized device which is fully implantable in the middle/inner ear and includes the following components: frequency selective accelerometer/flexible strain gauge, energy receiver or harvester unit, speech processor, and cochlear multielectrode. The aim of the PhD work is to design, fabricate, and characterize such microelectromechanical systems (MEMS), which have the potential to detect the acoustically induced vibrations in the middle ear. The MEMS device must fulfill several requirements: capability to detect low accelerations in the voice frequency range (0.3-3 kHz), frequency sensitivity to enable multichannel operation, low power consumption, small size and weight, biocompatibility etc. Two device concepts are planned to be investigated and compared: i) a piezocantilever-based device which is to be mounted on one of the ossicles (e.g. incus) and ii) a membrane type high electron mobility transistor (HEMS) which can measure the vibration of the eardrum.
The Nanosensors Lab of the Research Centre for Energy Research provides the experimental infrastructure for the research. Two semiconductor cleanrooms with complete Si MEMS and nanofabrication lines are available for the fabrication of the sensors, while the tests are carried in a dedicated vibration lab equipped with interferometric scanning vibrometer, anechoic test box, piezotester, piezoelectric and electromagnetic shakers etc. Besides, the project is supported by clinical doctors and by a cochlear implant manufacturing company.
Motivation for applied research, skills and patience for experimental work, good communication skills