Papers by Keyword: Piezoelectric Material

Abstract: This study issues the improvement of the parameters of manufacturing on the flexible SAW device. The better piezoelectric characteristics of ZnO film will be obtained. The Sol-Gel method is used to prepare the ZnO solution and deposits ZnO film by spin coating process. X-ray diffraction (XRD) and scanning electron microscope (SEM) are used to get the crystalline property. The results reveal that ZnO film possesses better crystalline property in 400RPM of spin speed. The piezoelectric intensity of (002) direction is 1566.67 (a.u.) and atomic morphology of ZnO film are exhibited by SEM image. This better ZnO film will enhance the wave propagation of surface acoustic wave (SAW) device. It can also expand the application of SAW device.

Abstract: Sol-gel method is used for the formation of Pb(Zr0.63Ti0.37)O3(PZT) thin films. The initial films were formed with spin coating sol solution on silicon wafer and drying coated wet sol film at 300°C for 5min. This process was repeated for 1-4 times to obtain 4 initial films with different thicknesses. 4 initial films were annealed at 500°C for 2h to obtain PZT ceramics films. The morphologies of the surface and cross-section of PZT films were observed with a scanning electronic microscope (SEM). The phase structures of PZT films were analyzed using an X-ray diffraction meter (XRD). Experimental results show that PZT film prepared by coating wet sol on silicon once can be high smooth and compact film.

Abstract: The thin film of (103)-oriented aluminum nitride (AlN) is an attractive piezoelectric material for the applications in film bulk acoustic wave resonator (FBAR) devices. Due to the bulk acoustic wave (BAW) properties of (103) oriented AlN films, it can excite a quasi-shear mode (velocity = 5,957 m/s, K² = 3.8%) that can be used for FBAR liquid sensor and even loss less than the FBAR device with (002) oriented AlN films. In this research, the (103) oriented AlN films were successfully deposited onto (100) silicon substrate by radio frequency (RF) magnetron sputtering. Different sputtering pressures (1m torr, 3m torr, 5m torr, and 7m torr) were discussed in this experiment process. Comparisons were made on their crystalline structures with X-ray diffraction (XRD) and the surface morphologies was investigated by the atomic force microscopy (AFM). The result exhibited the optimal sputtering pressure is 5m torr. The optimal (103) oriented AlN films have the strongest XRD intensity, the smallest full width at half maximum (FWHM) value (0.6°), the largest grain size (15.78nm) and the smooth surface roughness (Ra=3.259nm).

Abstract: The paper is investigated the polarization properties and mechanical behavior of new piezoelectric polymer material plates by experimental procedures and finite element analysis. In this study, the PVDF materials is used to produce the piezoelectric polymer layer and the coating film, we have provided a nice procedures for manufacturing piezoelectric polymer plates (PVDF). In order to find the proper proportion of the PVDF to achieve the best material properties, the mechanical behavior of displacements and stresses for the electrets is investigated by experimental measurement and finite element analysis (with ANSYS). It is investigated whether the thicknesses of specimens are affected the polarization. The paper is presented modal analysis techniques for piezoelectric thin plates.

Abstract: The paper investigats the polarization properties and mechanical behavior of new piezoelectric polymer material plates by experimental procedures and finite element analysis. In this study, the PVDF materials are used to produce the piezoelectric polymer layer and the coating film, we have provided nice procedures for manufacturing piezoelectric polymer plates (PVDF). In order to find the proper proportion of the PVDF to achieve the best material properties, the mechanical behavior of displacements and stresses for the electrets is investigated by experimental measurement and finite element analysis (with ANSYS). It is investigated whether the thicknesses of specimens will affect the polarization. The paper is presented modal analysis techniques for piezoelectric thin plates.

Abstract: A fit-to-data technique was proposed to identify the mechanical and piezoelectric parameters of a model involving a piezoelectric laminated composite beam. Analytical solutions for displacement of the model were derived for parameter identification. The parameter identification problem was formulated as the problem of minimizing the objective function defined as a square sum of differences between the measured displacement and the computed displacement by the analytical solutions. Levenberg-Marquardt method was used to solve the minimization problem. The sensitivities of displacements with respect to the parameters were based on the finite difference approximation method. Numerical example shows that the proposed technique for parameter identification is effective.

Abstract: In recent years, significant progress has been made with in-deep application of piezoelectric harvesting energy technology. To make the technology development more convenient, a comprehensive review on application of piezoelectric harvesting technology is made in the paper. Piezoelectric harvesting devices as power source from vibration, human motion and so on are expounded. The technology would bring fast increasing in systems of micro wireless sensor, integrated systems and self-power MEMS.

Abstract: In this paper, we analyze the influence of surface effects including residual surface stress, surface piezoelectric and surface elasticity on the buckling behavior of piezoelectric nanobeams by using the Timoshenko beam theory and surface piezoelectricity model. The critical electric potential for buckling of piezoelectric nanobeams with different boundary condition is obtained analytically. From the results, it is found that the surface piezoelectric reduces the critical electric potential. However, a positive residual surface stress increases the critical electric potential. In addition, the shear deformation reduces the critical electric potential, and the influence of shear deformation become more significant for a stubby piezoelectric nanobeam.

Abstract: Micro-gripper is a key module in IC/LED wire bonding. The paper presents a micro-gripper combining with piezoelectric material and flexible structure. The dynamic and static characteristics of the micro-gripper are calculated by finite element method, and the natural frequencies, the vibration modes, as well as the deflection range of the micro-gripper are obtained. In the experiment, the high-speed camera was used to track the vibration of the micro-gripper, and the relationship between deflection range and driven voltage was established. The vibration behavior was measured by a non-contact laser measuring device. These results can help improve the reliability of the micro-gripper used in wire bonding.

Abstract: With the development of science and technology, the smaller sizes generator, the more attention by people. The main purpose of this article is to manufacture three-phase nanogenerator and piezoelectric nanogenerator under vibration, and their working principle are introduced and their performances are studied. The results show that, using the present nanomaterials, three-phase nanogenerator and piezoelectric nanogenerator can be prepared. In ambient vibration condition, piezoelectric materials produce larger rated current and voltage. However, copper laps cutting magnetic line of force produce less rated current and voltage. So the piezoelectric nanogenerator can be separately used to supply power. It may produce higher voltage, current and power if three-phase nanogenerator and piezoelectric nanogenerator in series-parallel connection, and there is commercial value.