Details

Autor(en) / Beteiligte

• Gong, Zhenfeng
• Li, Haie
• Jiang, Xu
• Wu, Guojie
• Gao, Tianli
• Guo, Min
• Ma, Fengxiang
• Chen, Ke
• Mei, Liang
• Peng, Wei
• Yu, Qingxu

Titel

A Miniature Fiber-Optic Silicon Cantilever-Based Acoustic Sensor Using Ultra-High Speed Spectrum Demodulation

Ist Teil von

• IEEE sensors journal, 2021-09, Vol.21 (18), p.20086-20091

Ort / Verlag

New York: IEEE

Erscheinungsjahr

2021

Quelle

IEEE Xplore

Beschreibungen/Notizen

• A silicon cantilever-based fiber-optic acoustic sensor (FOAS) is presented in this work. A rectangular cantilever is fabricated upon a silicon-on-insulator (SOI) wafer using a micro-electro-mechanical system (MEMS). The length, width and thickness of the silicon cantilever are <inline-formula> <tex-math notation="LaTeX">530~\mu \text{m} </tex-math></inline-formula>, <inline-formula> <tex-math notation="LaTeX">200~\mu \text{m} </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">3~\mu \text{m} </tex-math></inline-formula>, respectively. The resonant frequency of the silicon cantilever is 14820 Hz with a sensitivity of 950 nm/Pa. An ultra-high speed absolute cavity length demodulation method is adopted using a complementary metal oxide semiconductor (CMOS) spectrometer and an 850 nm superluminescent light emitting diode (SLED). A modified Buneman frequency estimation and total phase demodulation algorithm is adopted. The frequency response curve shows a relatively flat trend from 20 Hz to 13 kHz. The sensor exhibits good linearities at different frequencies while the applied acoustic pressure is increased from 0 Pa to 2.5 Pa. Experimental results indicate that the minimum detectable pressure (MDP) of the proposed FOAS is calculated to be <inline-formula> <tex-math notation="LaTeX">25.68~\mu </tex-math></inline-formula>Pa/Hz 1/2 at the frequency of 13 kHz. The silicon cantilever-based FOAS achieves broad operating bandwidth, high sensitivity, small size, and good stability.