A MEMS acoustic energy harvester

This paper presents the development of a micromachined acoustic energy harvester for aeroacoustic applications. The acoustic energy harvester employs a silicon-micromachined circular, piezoelectric composite diaphragm for electroacoustic transduction. Lumped element modeling, design, fabrication and characterization of a micromachined acoustic energy harvester prototype are presented. Experimental results indicate a maximum output power density of 0.34 µW cm −2 at 149 dB (ref. 20 µPa) and suggest a potential output power density, for this design, of 250 µW cm −2 with an improved fabrication process.