Study of a Ferroelectrics-Silicon Integrated Microspeaker and Microspeaker Array

ABSTRACT

A novel ferroelectrics-silicon integrated microspeaker and microspeaker array is proposed. The Al/SiO₂/Pt/Pb(Zr,Ti)O₃/Pt/Ti/SiO₂ multimorph structure is designed and fabricated. The microspeaker based on this multimorph structure has high output acoustic pressure, and the displacement at the center of membrane is very high. This structure designed in the single microspeaker can also be used in microspeaker array. After optimization of the position of the electroacoustical transducer cells, the realized microspeaker array can reach the high output acoustic power and good transducing directivity. This integrated microspeaker and microspeaker array will be widely used for audio frequency and ultrasonic frequency devices.

Keywords:

• Ferroelectrics-silicon integration
• PZT
• multimorph structure
• microspeaker
• microspeaker array

ACKNOWLEDGEMENTS

The authors would like to thank Ningxin Zhang for his help with PZT fabrication, as well as Xiaoming Wu and Xun Zhang for their help with testing. We also thank members of the Devices Research Division of Institute of Microelectronics of Tsinghua University for their support and contributions to this research.