Electronic Materials Letters

, Volume 14, Issue 2, pp 101–111 | Cite as

Characterization of a Piezoelectric AlN Beam Array in Air and Fluid for an Artificial Basilar Membrane

  • Hyejin Jeon
  • Jongmoon Jang
  • Sangwon Kim
  • Hongsoo Choi


In this study, we present a piezoelectric artificial basilar membrane (ABM) composed of a 10-channel aluminum nitride beam array. Each beam varies in length from 1306 to 3194 μm for mimicking the frequency selectivity of the cochlea. To characterize the frequency selectivity of the ABM, we measured the mechanical displacement and piezoelectric output while applying acoustic stimulus at 100 dB sound pressure level in the range of 500 Hz–40 kHz. The resonance frequencies measured by mechanical displacement and piezoelectric output were in the range of 10.56–36.5 and 10.9–37.0 kHz, respectively. In addition, the electrical stimulus was applied to the ABMs to compare the mechanical responses in air and fluid. The measured resonance frequencies were in the range of 11.1–47.7 kHz in the air and 3.10–11.9 kHz in the fluid. Understanding the characteristics of the ABM is important for its potential use as a key technology for auditory prostheses.

Graphical Abstract


Artificial basilar membrane (ABM) Piezoelectric AlN Frequency selectivity XeF2 dry etching Residual stress 



The authors would like to thank Center for Core Research Facilities of DGIST for technical support. This work is funded by the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (2014M3C1A9060874, 17-BD-0404) and by the DGIST R&D Program of the Ministry of Science.


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Copyright information

© The Korean Institute of Metals and Materials 2018

Authors and Affiliations

  • Hyejin Jeon
    • 1
    • 2
  • Jongmoon Jang
    • 1
    • 2
    • 3
  • Sangwon Kim
    • 1
    • 2
  • Hongsoo Choi
    • 1
    • 2
  1. 1.Department of Robotics EngineeringDaegu Gyeongbuk Institute of Science and Technology (DGIST)DaeguKorea
  2. 2.DGIST-ETH Microrobot Research Center, DGISTDaeguKorea
  3. 3.Microsystems LaboratoryÉcole Polytechnique Fédérale de LausanneLausanneSwitzerland

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