Design of a totally implantable artificial cochlea mimicking the human hearing mechanism

In this research, a bio-inspired artificial cochlea will be designed based on the artificial basilar membrane and the nanowire mimicking stereocilia. It has the potential to be used for the totally implantable artificial cochlea. We developed the FEM models to simulate the behavior of the artificial basilar membrane to understand the frequency separation mechanism of the human basilar membrane. The exponentially tapered membranes with several thicknesses were designed using silicon nitride (Si₃N₄) and polyimide (PI). All the exponentially tapered membranes successfully showed the frequency shifting effect and the models were effectively used for optimizing the design of the artificial basilar membrane. We fabricated the ZnO nanowires mimicking the stereocilia in various sizes and measured the piezoelectric potential output of the ZnO nanowires. The mechanism of the ZnO nanowires was also understood through the FEM simulation. It was concluded that ZnO nanowires can generate electric current by the piezoelectric effect and ZnO nanowires have potential to be used as a power source for nano-scale devices. To conclude, the work is concentrated on the design of the artificial basilar membrane and the piezoelectric ZnO nanowires for the artificial mechanosensory system.