The Transactions of The Korean Institute of Electrical Engineers (전기학회논문지)

The Korean Institute of Electrical Engineers (대한전기학회)
권호 표지

Piezoelectric Microspeakers Fabricated with High Quality AlN Thin Film

고품질 AlN 박막으로 제작한 압전 마이크로스피커

  • 이승환 (충주대학교 공대 기계공학과/친환경 에너지 부품소재센터) ;
  • 정경식 (충주대학교 공대 대학원 기계공학과) ;
  • 김동기 (대진전자(주) 연구소) ;
  • 신광재 ((주)엠에스솔루션 연구소)
  • Published : 2007.08.01
Download PDF
⟨ Previous Next ⟩

Abstract

This paper reports the piezoelectric microspeakers that are audible in open air with high quality piezoelectric AlN thin film deposited onto Mo/Ti electrode. This successful achievement, compared to the previous results, is followed by manipulating two material properties: the one is to use a compressively stressed silicon nitride film as a supporting diaphragm (even tensile stressed, around +20 MPa) and the another is to use high quality AlN thin film with compressive residual stress (less than -100 MPa). With these materials, the Sound Pressure Level (SPL) of the fabricated micro speakers shows more than 60 dB from 100 Hz to 15 kHz and the highest SPL is about 100 dB at 9.3 kHz with 20 Vpeak-to-peak sinusoidal input and with 10 mm distances from the fabricated micro speakers to the reference microphone (B&K Type 2669 & 4192L).

Keywords

References

  1. B.M. Diamond, J.J. Neumann Jr., and K.J. Gabriel, 'Digital sound reconstruction using array of CMOS-MEMS microspeakers', in Tech. Digest of IEEE 15th International MEMS conference, pp.296, 2002
  2. S.S. Lee, R.P. Ried and R.M. White, 'Piezoelectric Cantilever Microphone and Microspeaker', J. MEMS, vol. 5, no.4, pp. 238, 1996
  3. C.H. Han and E.S. Kim, 'Parylene-Diaphragm Piezoelectric Acoustic Transducers', in Tech. Digest of IEEE .l3th International MEMS conference, pp. 148, 2000
  4. Li-Tian, L. Zhi- Jian, L. Tian-Ling, and R. Lin-Tao, 'Design of a New PZT Based Microphone and Microspeaker' Ferroelectrics, vol. 259-264, pp. 55, 2001
  5. C.H. Chou, Y.C. Lin, J.H. Huang, N.H. Tai, and LN. Lin, 'Growth of high quality AIN thin films on diamond using TiN/Ti buffer layer', J. Diamond and Related Materials, vol. 15, pp.404, 2006 https://doi.org/10.1016/j.diamond.2005.07.032
  6. M.Benetti, D.C. Cannata, F. Di Pietrantonio, and E. Verona, A. Generosi, B.Paci and V.Rossi Albertini, 'Growth and Characterization of piezoelectric AlN thin films for diamond-based surface acoustic wave devices', Thin Solid Films, vol. 497, pp.304, 2006 https://doi.org/10.1016/j.tsf.2005.10.073
  7. J. Olivares, E. Iborra, M.Clement, L. Vergara, J. Sanrador and A. Sanz-Hervas, 'Piezoelectric actuation of microbridges using AIN', Sensors and Actuators A, vol.123-124, pp. 590, 2005
  8. S.H. Yi and E.S. Kim, 'Micromachined Piezoelectric Microspeaker', Jpn. J. Appl. Phys., vol.44, no. 6A, pp.35-36, 2005
  9. A. K. Sinha and T. T. Sheng, 'The temperature dependence of stresses in aluminum film on oxidized silicon substrates', Thin Solid Films, vol.48, pp.118, 1978
  10. O. Tabata, K Kawahata, S. Sugiyama and I. Igarashi, 'Mechanical Property Measurements of Thin Film Using Load-Deflection of Composite Rectangular Membranes', Sensors and Actuators, vol.20, pp.135, 1989