Improved MEMS microphone frequency response through design-optimization
Abstract
Microphone main characteristic is to faithfully detect and transform incoming acoustic signal in electric one. Semiconductor based capacitive MEMS microphones, despite their limited dimensions, offer remarkable performances (frequency response, SNR). The purpose of this article is to introduce some design optimizations in the current SDM (Sealed-Dual-Membrane) capacitive MEMS microphone mainly concerning the position of the ventilation hole. The effects of the suggested modifications on the microphone’s performances were evaluated using Lumped Model simulation tool. A clear improvement in the device frequency response within audio-band was obtained even if a less significant improvement in the general performances of microphone (SNR) was achieved.
Keywords
capacitive MEMS microphone, frequency response, lumped model, ventilation hole, back-volume.
Supporting Institution
Sakarya Uygulamalı Bilimler Üniversitesi
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