Piezoelectric micro-energy harvester integrated with CMOS energy extraction circuits : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Engineering at Massey University, Auckland, New Zealand. EMBARGOED until 5 November 2027.

Abstract

Conventional pressure monitoring sensors used in biomedical applications, such as blood pressure and left ventricular systolic pressure measurements, have significant drawbacks, including high power consumption that shortens battery life and contributes to increased costs. A multifunctional piezoelectric transducer has been implemented for self-powered pressure sensing and energy harvesting (EH), eliminating the need for a separate transducer for pressure sensing and energy harvesting. This approach optimizes resources and reduces costs. The piezoelectric EH/sensor uses a lead-free, biocompatible, high-performance aluminum nitride (AlN) transducer. This article presents comprehensive physics-based mathematical modelling and numerical simulations that deliver optimized design parameters for a novel piezoelectric thin-film MEMS transducer energy-converter for improved pressure sensitivity and power density. The experimental results show a sensitivity of 0.06 V/kPa and a power density of 1.1 mW/cm³.--Shortened abstract