Radiation impedance study of a capacitive micromachined ultrasonic transducer by finite element analysis


BAYRAM B.

JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA, cilt.138, sa.2, ss.614-623, 2015 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 138 Sayı: 2
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1121/1.4923361
  • Dergi Adı: JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.614-623
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

In this study, radiation impedance of a capacitive micromachined ultrasonic transducer composed of square-shaped membranes arranged in m x m configuration (m = 1 - 5) is investigated using finite element analysis (FEA) of a commercially available software package (ANSYS). Radiation impedance is calculated for immersed membranes operating in conventional and collapse modes. Individual membrane response within the multi-membrane configuration is analyzed, and excited modes and their effects on radiation impedance and the pressure spectra are reported. This FEA provides an accurate behavior of the acoustic coupling of a thin membrane in a multi-membrane configuration, and extends above the anti-resonance frequency. The first resonance frequency of the membrane is excited for m x m (m >= 3) configuration in conventional mode and for m x m (m >= 2) configuration in collapse mode. Therefore, this frequency is determined to be responsible for the adverse effects observed in radiation impedance and pressure spectrum. A membrane configuration, which is missing the central membrane from the full m x m configuration is proposed, and is investigated with the FEA. This study is beneficial for the design of precise transducers suited for biomedical applications. (C) 2015 Acoustical Society of America.