A new measurement microphone based on MEMS technology

TLDR

The study introduces a MEMS‑based measurement microphone. The microphone employs a silicon chip with custom packaging and is evaluated for sensitivity, noise, frequency response, and environmental robustness. Measured sensitivity of 22 mV/Pa (–33 dB re 1 V/Pa) and noise of 23 dB(A), 7 dB below state‑of‑the‑art, with uniform frequency response and comparable environmental immunity, demonstrates superior noise performance.

Abstract

This paper presents a new type of measurement microphone that is based on MEMS technology. The silicon chip design and fabrication are discussed, as well as the specially developed packaging technology. The microphones are tested on a number of key parameters for measurement microphones: sensitivity, noise level, frequency response, and immunity to disturbing environmental parameters, such as temperature changes, humidity, static pressure variations, and vibration. A sensitivity of 22 mV/Pa (-33 dB re. 1 V/Pa), and a noise level of 23 dB(A) were measured. The noise level is 7 dB lower than state-of-the-art 1/4-inch measurement microphones. A good uniformity on sensitivity and frequency response has been measured. The sensitivity to temperature changes, humidity, static pressure variations and vibrations is fully comparable to the traditional measurement microphones. This paper shows that high-quality measurement microphones can be made using MEMS technology, with a superior noise performance.