Title :
Experimental investigation of electrostatic ultrasonic transducers with grooved backplates
Author :
Pizarro, L. ; Certon, D. ; Lethiecq, Marc ; Boumatar, O. ; Hosten, B.
Author_Institution :
LUSSI, GIP Ultrasons, Tours, France
Abstract :
This paper presents an experimental investigation of electrostatic transducers with grooved backplates for airborne applications. These transducers consist of a micromachined conductor backplate covered with a metal-coated polymer film. Measurements such as pulse electro-acoustic response, electrical impedance and mechanical displacement field over the membrane have been performed. The influence of the groove layout on the transducer behaviour and its performances is studied. Two different behaviours in the spectral response are observed. One, due to the mechanical resonance of the membrane over the groove and the other one, produced by the polished backplate surface. A method to control the sensitivity and bandwidth of these transducers by an appropriate choice of the grooved surface ratio is proposed
Keywords :
acoustoelectric transducers; electrostatic devices; micromachining; ultrasonic transducers; airborne application; bandwidth; electrical impedance; electrostatic ultrasonic transducer; grooved backplate; mechanical displacement; mechanical resonance; membrane; metal-coated polymer; micromachined conductor; polished surface; pulse electroacoustic response; sensitivity; spectral response; Biomembranes; Conductive films; Displacement measurement; Electric variables measurement; Electrostatic measurements; Impedance measurement; Mechanical variables measurement; Polymer films; Pulse measurements; Ultrasonic transducers;
Conference_Titel :
Ultrasonics Symposium, 1997. Proceedings., 1997 IEEE
Conference_Location :
Toronto, Ont.
Print_ISBN :
0-7803-4153-8
DOI :
10.1109/ULTSYM.1997.661750
