This work aims for utilizing human ocular motion for the self-sufficient power supply of a minimally invasive implantable monitoring system for intraocular pressure (IOP). With a proven piezoelectric functionality (d(33) > 5 pm/V), nanocrystalline thin films of aluminum nitride (AlN) provide a good capability for micromechanical energy harvesting (EH) in medical applications. Many d31-mode microcantilever architectures are poorly suited for human-induced EH: Resonant mass-spring-damper systems are tested under high, narrow-band excitation frequencies. However, human motions, e.g. vibrations of eyeballs are marked by their low frequency, unpredictable, mainly aperiodic and time-varying signature. Different vibration types and directions are 3-dimensionally superimposed. Saccadic eye movements are favorable for inertial microgenerators because of their high dynamic loading w

In this work, we show that thin biocompatible AlN films reveal a stable, frequency independent piezoresponse demonstrating a good applicability for implantable micro-generators. It was demonstrated that although more power is generated by resonant (tensile stressed) systems, e.g. cantilevers and planar membranes, the non-resonant (compressive stressed) systems, e.g. corrugated membranes, are preferable for this purpose due to the generation of sufficient power at low-frequency aperiodic vibrations and at very low accelerations

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