Piezoelectricity in multi-air voids electrets

Author

Altafim, R.A.C. ; Basso, H.C. ; Neto, L. Goncalves ; Lima, L. ; Altafim, R.A.P. ; de Aquino, C.V.

Author_Institution

Eng. Sch. of Sao Carlos, Sao Paulo Univ., Brazil

fYear

2005

fDate

16-19 Oct. 2005

Firstpage

669

Lastpage

672

Abstract

Multi-air voids space-charge electrets have been developed using two fluorethylenepropylene (Teflon-FEP) films. In this work, a new technique developed to assembler these films allows the control of the thickness and shapes of multi-air voids distributed on their surface. When an impulse voltage process charges these voids, it is possible to obtain samples with high piezoelectric coefficients. To explain this piezoelectric characteristic, a theoretical explanation based on the electret microphone mechanism is introduced. Measurements show the piezoelectric coefficients for different frequencies.

Keywords

electrets; microphones; piezoelectric materials; piezoelectric thin films; piezoelectricity; polymer films; space charge; thickness control; electret microphone mechanism; fluorethylenepropylene films; impulse voltage process; multi-air void electret; piezoelectric coefficients; piezoelectricity; space-charge electrets; Assembly; Electrets; Ferroelectric materials; Microphones; Piezoelectric films; Piezoelectricity; Polymers; Shape control; Surface charging; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Electrical Insulation and Dielectric Phenomena, 2005. CEIDP '05. 2005 Annual Report Conference on

Print_ISBN

0-7803-9257-4

Type

conf

DOI

10.1109/CEIDP.2005.1560771

Filename

1560771