TY - GEN
T1 - A Novel High-SNR Full Bandwidth Piezoelectric MEMS Microphone Based on a Fully Clamped Aluminum Nitride Corrugated Membrane
AU - Bosetti, Gabriele
AU - Bretthauer, Christian
AU - Bogner, Andreas
AU - Krenzer, Michael
AU - Gierl, Karolina
AU - Timme, Hans Joerg
AU - Heiss, Heinrich
AU - Schrag, Gabriele
N1 - Publisher Copyright:
© 2023 IEEJ.
PY - 2023
Y1 - 2023
N2 - We present an innovative design and the related fabrication method for a high-SNR piezoelectric MEMS microphone based on fully clamped corrugated aluminum nitride (AlN) membrane. The corrugations allow for effective intrinsic stress relaxation and additionally enable differential signal generation by exploiting a pseudo-bimorph effect. Two distinct designs are compared against a state-of-the-art commercial cantilever-based piezoelectric MEMS microphone of same die and similar package size. We show that, in contrast to the commercial microphone, a resonance-free system response up to 20 kHz can be achieved and the low-frequency-roll-off (LFRO) is tightly defined by lithography and independent of intrinsic stress variation. Finally, albeit higher system resonance, the new concept shows superior signal-to-noise ratio (SNR) values with a maximum of 62.61 dB(A) and a sensitivity of -47.11 dBV/Pa.
AB - We present an innovative design and the related fabrication method for a high-SNR piezoelectric MEMS microphone based on fully clamped corrugated aluminum nitride (AlN) membrane. The corrugations allow for effective intrinsic stress relaxation and additionally enable differential signal generation by exploiting a pseudo-bimorph effect. Two distinct designs are compared against a state-of-the-art commercial cantilever-based piezoelectric MEMS microphone of same die and similar package size. We show that, in contrast to the commercial microphone, a resonance-free system response up to 20 kHz can be achieved and the low-frequency-roll-off (LFRO) is tightly defined by lithography and independent of intrinsic stress variation. Finally, albeit higher system resonance, the new concept shows superior signal-to-noise ratio (SNR) values with a maximum of 62.61 dB(A) and a sensitivity of -47.11 dBV/Pa.
KW - Corrugated Membrane
KW - Differential Readout
KW - Piezoelectric MEMS Microphone
KW - Piezoelectric Thin-Films
UR - https://www.scopus.com/pages/publications/85191196490
M3 - Conference contribution
AN - SCOPUS:85191196490
T3 - 2023 22nd International Conference on Solid-State Sensors, Actuators and Microsystems, Transducers 2023
SP - 366
EP - 369
BT - 2023 22nd International Conference on Solid-State Sensors, Actuators and Microsystems, Transducers 2023
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 22nd International Conference on Solid-State Sensors, Actuators and Microsystems, Transducers 2023
Y2 - 25 June 2023 through 29 June 2023
ER -