Akbar Ghasemi Yeklangi - Department of material engineering, Tarbiat Modares University, Tehran, Iran.
Siamak Esmaeelzadeh Khadem - Department of mechanical engineering, Tarbiat Modares University, Tehran, Iran.
Vahid Ahmadi - Department of electrical engineering, Tarbiat Modares University, Tehran, Iran.

Piezoelectric polymer materials are good sensors for sensing strain, temperature, electronic charge/discharge and acoustic waves. Polyvinylidenefluoride (PVDF), in its β-phase, isknown for its piezo- and pyroelectric properties [1]. PVDF has been quite extensively used in sensing applications. Sensorapplications of PVDF found in existing literature are related to nondestructive testing and acoustic emission monitoring [2]. There are number of research papers that have focused on the use of PVDF in wide range of applications such as weight, pressure and image sensor [3]. Since PVDF is flexible and canbe easily shaped and patterned (with printed electrodes), it is ideally suited for sensing of structural vibration [3]. PVDFfilms have many orders lower mechanical impedance and lower electrical impedance due to lower stiffness and smaller thickness compared to piezo-ceramics like PZT so it has the potential of being used as ultrasonic sensor. The present paper is an attempt toward such development