Micro-acoustic source for hearing applications fabricated with 0.35μm CMOS-MEMS process

We report on a micro-acoustic source based on industrial 0.35 mu m CMOS-MEMS process with only one additional post-process step. The fabrication flow completed with the characterization results of an electrostatic micro-acoustic source based on 0.35 mu m CMOS process with sacrificial SiO2 etch is shown here for the first time. The acoustic pressure in air in the vicinity of the resonant frequency (32,2 kHz) at the distance of 10 mm from the source was measured. The acoustic pressure of 12 mPa was obtained when the source was driven by AC signal of 6 Vp-p and the DC bias of 8 V. (C) 2015 The Authors. Published by Elsevier Ltd.