Projekte -> Piezo Microphone Array
Successfully validated on Airbus BACCHUS aeroacoustic test bench
Dual-frequency Aluminum Scandium Nitride piezoelectric microphones with wide bandwidth, large dynamic range, and high sensitivity for wind tunnel testing
https://ieeexplore.ieee.org/abstract/document/10516769
World’s Highest-Performance Dual-Frequency AlScN Piezoelectric MEMS Microphone for Aeroacoustic Wind-Tunnel Testing Silicon Austria Labs (SAL) + University of South-Eastern Norway First author: Dr. Yanfen Zhai
Extreme Fabrication Challenge – Perfectly Delivered
Full 4-inch SOI wafer, complex 8-mask high-precision process including deep backside cavity, vapor HF release, and stress-controlled AlScN/Mo multilayer stack
First-ever 30 % scandium-doped AlScN (AlSc30%N) thin-film MEMS microphone
Dual cantilever design (0.94 mm² + 0.36 mm²) on single chip covering two frequency decades
Dual-frequency AlSc30%N piezoelectric microphones with wide bandwidth, large dynamic range, and high sensitivity for wind tunnel testing
https://ieeexplore.ieee.org/abstract/document/10516769
World’s Highest-Performance Dual-Frequency AlScN Piezoelectric MEMS Microphone for Aeroacoustic Wind-Tunnel Testing Silicon Austria Labs (SAL) + University of South-Eastern Norway
author: Dr. Yanfen Zhai Prof.Lixiang Wu
Extreme Fabrication Challenge – Perfectly Delivered
- First-ever 30 % scandium-doped AlScN (AlSc30%N) thin-film MEMS microphone
- Dual cantilever design (0.94 mm² + 0.36 mm²) on single chip covering two frequency decades
- Full 4-inch SOI wafer, complex 8-mask high-precision process including deep backside cavity, vapor HF release, and stress-controlled AlScN/Mo multilayer stack
Result – First Wafer, Zero Failure
- Turnaround time: only 3 weeks from layout to fully packaged working devices
- 100 % yield across the entire wafer
- Sensitivity: 3.2 mV/Pa (100× higher than previous AlN state-of-the-art)
- Bandwidth: 300 Hz – > 55 kHz (flat response)
- Dynamic range: > 147.7 dB SPL (no DC bias required)
- SNR: 60.2 dB
- Successfully validated on Airbus BACCHUS aeroacoustic test bench
Currently the highest sensitivity and widest bandwidth piezoelectric MEMS microphone ever reported for professional wind-tunnel applications.
| Metric | Target specification | State of the art | |
| Sensing element size | 600 µm×1000 µm (900 um×1450 um) | 828 µm diameter | 0.96 mm2 |
| Bandwidth | 100 Hz – 100 kHz (>50 kHz) | 69 Hz – 20 kHz | 100 Hz – 10 kHz |
| Sensitivity | 5-10 mV/Pa (5.35mV/pa) | 32-44 µV/Pa | 7.9 mV/Pa |
| Dynamic range | 30-170 dB SPL (>150 dB SPL) | 40-172 dB SPL | 127 dB AOP |
| Signal-to-Noise Ratio | 64 dB (ref. 94 dB SPL)* (65 dB) | N/A | 66-68 dB |
| Application | Aeroacoustic measurement | Aeroacoustic measurement | Consumer electronics |
| MEMS structure | Two couples of similar triangle cantilevers | Circular membrane | Uniformly sectored cantilevers |
| Piezoeelectric material | Multilayer AlScN | Bilayer AlN | Bilayer AlN |