고품질 AlN 박막으로 제작한 압전 마이크로스피커

Piezoelectric Microspeakers Fabricated with High Quality AlN Thin Film

  • 이승환 (충주대학교 공대 기계공학과/친환경 에너지 부품소재센터) ;
  • 정경식 (충주대학교 공대 대학원 기계공학과) ;
  • 김동기 (대진전자(주) 연구소) ;
  • 신광재 ((주)엠에스솔루션 연구소)
  • 발행 : 2007.08.01

초록

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).

키워드

참고문헌

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