Electrical Characteristics of Chemical Solution Deposited Nd 3+ Doped PZT (53/47) Thin Films in Planar Electrode Configu
- PDF / 403,097 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 103 Downloads / 180 Views
Electrical Characteristics of Chemical Solution Deposited Nd3+ Doped PZT (53/47) Thin Films in Planar Electrode Configuration S.B. Majumder, B. Perez, B. Roy, A. Martinez, and R.S. Katiyar PO Box 23343, Department of Physics, University of Puerto Rico San Juan, PR 00931, USA ABSTRACT Electrical characteristics of ferroelectric thin films in planar electrode configuration are important to characterize these materials for their applications in micro electro mechanical (MEM) and tunable microwave devices. In the present work we have prepared polycrystalline Pb1-3x/2Ndx(Zr0.53Ti0.47)O3 (x = 0.0 to 10.0 at %) thin films on platinized silicon substrate by chemical solution deposition (CSD) technique. The films were characterized in terms of their dielectric and ferroelectric properties by depositing planar interdigital finger electrodes on the surface of the films by electron beam lithography. The capacitance and loss tangent of undoped and 4 at % Nd doped PZT films measured at 100 kHz were found to be 138 pF, 0.033 and 95 pF, 0.019 respectively. Saturated hysteresis loops were obtained in undoped PZT film by applying 100 V across 10 µm electrode separation. Nd doped PZT films on the other hand, electrically shorted at comparatively lower voltage. The electrical characteristics of these films are correlated with their phase formation behavior and microstructural features.
INTRODUCTION Smart materials can sense and accordingly respond to a variety of external stimuli such as pressure, electric and magnetic fields, temperature, nuclear radiation etc. Devices made of smart materials such as actuators and sensors are integral part of a smart system. The family of smart material include piezoelectric and electrostrictive materials, polymers, shape memory alloys, electro-rheological fluids, optical fibers etc. Among these materials piezoelectric materials are attractive for the design of smart devices due to large strain yield, high response speed, reasonable electro-mechanical efficiency, inexpensive and light weight and they can be easily shaped, bonded or embedded in a variety of surfaces [1]. Piezoelectric materials are non-centrosymmetric and posses permanent electric dipole. Due to direct piezoelectric effect the piezoelectric material can generate electrical charge (voltage) when an external stress is applied to it. On the other hand, due to the converse piezoelectric effect the piezoelectric materials are strained when an external electrical field is applied to it. Sensors and actuators are fabricated exploiting the direct and converse piezoelectric effect respectively. Utilizing bulk piezoelectric materials cantilever mounted (unimorph / bimorph), multi-layer, and Moonie type actuators have been designed. Irrespective of the adopted design in all the piezo-actuators the characteristic parameters are (i) degree of displacement, (ii) magnitude of the generative force and (iii) response speed (resonance frequency). For efficient actuator performance large possible generative displacement and force are desired. A bending
Data Loading...
