상세정보
학술지
The Effects of Electrodes Patterned onto the Piezoelectric Thin Film on Frequency Response Characteristics of PMN-PT MEMS Acoustic Actuators
- 발행일
- 201512
- 출처
- Journal of Electroceramics, v.35 no.1, pp.45-52
- ISSN
- 1385-3449
- 출판사
- Springer
- 협약과제
- 14PB4400, 슬림 스마트 기기용 초박형 압전 세라믹 스피커 기술 개발, 김혜진
- 초록
- The piezoelectric acoustic actuators were fabricated with PMN-PT single crystal membranes patterned by circular inter-digitated electrodes (IDEs) using silicon-based microelectromechanical systems (MEMS) technology. In order to investigate the effect of the electrodes patterned onto the PMN-PT membrane on the performance of the fabricated piezoelectric MEMS acoustic actuators, we simulated and analyzed the vibrational frequency response characteristics of the PMN-PT acoustic actuators with three different electrode diameters of 4, 6 and 8혻mm. The PMN-PT piezoelectric acoustic actuators had a dimension of 11.7 × 11.7혻mm2, and the 10혻μm-thick and 8.5혻mm-diameter PMN-PT membranes were formed by the backside etching process using both KOH silicon wet etching and Deep RIE equipment. From the simulated and measured results, it was shown that the vibrational displacement of the PMN-PT MEMS acoustic actuator can be improved with increasing area of the IDE patterned on the piezoelectric membrane. Moreover, the output sound pressure levels (SPLs) of the fabricated PMN-PT MEMS acoustic actuators were also improved with increasing areas of electrodes patterned on the piezoelectric membranes. Particularly, in a low-frequency range of less than 1혻kHz, the PMN-PT piezoelectric MEMS acoustic actuator with an electrode diameter of 8혻mm generated about 15혻dB higher sound pressures compared to the piezoelectric acoustic actuator with an electrode diameter of 4혻mm. These results reveal that not only the displacement characteristics but also the output sound performance of the PMN-PT MEMS acoustic actuator can be improved with increasing area of IDE patterned on the d33 mode piezoelectric membrane.
- KSP 제안 키워드
- Acoustic actuator, Deep RIE, Displacement characteristics, Electrode diameter, Etching process, Frequency response(FreRes), Frequency response characteristics, Micro-electro-mechanical system(MEMS), PMN-PT single crystal, Piezoelectric membrane, Piezoelectric thin film