ELECTRIC FIELD MICROSENSOR BASED ON THE STRUCTURE OF PIEZOELECTRIC INTERDIGITATED CANTILEVER BEAMS

This paper presents the design, fabrication, and preliminary experimental result of an electric field microsensor based on the structure of piezoelectric interdigitated cantilevers with staggered vertical vibration mode. The working principle of this electric field microsensor is demonstrated, and the induced charges and structural parameters of this microsensor are simulated by the finite element method. The electric field microsensor was fabricated by Micro-Electro Mechanical Systems(MEMS) technique. Each cantilever is a multilayer compound structure(Al/Si3N4/ Pt/PZT/Pt/ Ti/SiO 2/Si), and Piezoelectric, PieZ oelectric ceramic Transducer(PZT)(PbZ rxTi(1–x)O3) layer, prepared by sol-gel method, is used as the piezoelectric material to drive the cantilevers vibrating. This electric field microsensor was tested under the DC electric field with the field intensity from 0 to 5×104 V/m. The output voltage signal of the electric field microsensor has a good linear relationship to the intensity of applied electric field. The performance could be improved with the optimized design of structure, and reformative fabrication processes of PZT material.

Photoluminescence characteristics of soft PZT 53/47 ceramic doped at A and/or B sites

This study presents the photoluminescence characteristics of the PZT 53/47 system doped at A and/or B sites, with Nb(PZTN), La(PLZT), and Nb–La(PLZTN) in the concentration range from 0.2 to 1.0 molar fraction. The intensity of the emission bands of the system PZTN is two orders higher than the intensity of the emission bands of the systems PLZT and PLZTN, and these emission bands are located at 1.73 eV(718 nm), 2.56 eV(485 nm), and 2.93 eV(424 nm). The origin of the luminescence in these systems is associated with lead and oxygen vacancies produced during the sintering process. The results from X-ray diffraction(XRD) show a mixture of rhombohedral and tetragonal phases. The system PZTN shows a higher tetragonal phase concentration, while PLZT and PLZTN systems show a higher rhombohedral phase concentration. The cell volume shows an increase with dopant concentration only in the case of the PLZTN system. The band gap energy shows a small variation in the PZTN and PLZTN cases around 3.0 eV, a close value to the band gap energy of the pure PZT 53/47 sample. The system PLZT shows an increasing behavior until 4.41 eV for the higher dopant concentration.

Soft modes condensation in Raman spectra of(Pb-La)(Zr-Sn-Ti)O_(3)ceramics

Low frequency Raman spectra of(Pb_(0.97)La_(0.02)T(Zr_(0.864)Sn_(0.04)Ti_(0.096))O_(3)ceramic samples have been studied near cubic to antiferroelectric phase transition at about 200℃.A set of low frequency soft modes were observed restoring below the transition point,in addition to the known one above 100 cm^(-1).These modes show strong damping anomalies at the transition point that supposes considerable intermode interactions via dampings.

Parameters and design optimization of the ring piezoelectric ceramic transformer

Main aim of the presented paper is the theoretical analysis and experimental verification of the transformation parameters for the new type of nonhomogeneously poled ring transformer.The input part is poled in the thickness direction and output part in the radial direction.Two transformer geometries are studied—the input part is at inner ring segment,or it is at the outer ring segment.The optimum electrode size aspect ratios have been found experimentally as d_(1)=D≈0:60-0:65 for the ring with aspect ratio d=D¼0:2.The fundamental as well as higher overtone resonances were studied for the transformation ratio,the optimum resistive load,efficiency and no-load transformation ratio.Higher overtones have better transformation parameters compared to the fun-damental resonance.The new type ring transformer exhibits very high transformation ratios up to 200 under no-load and up to 13.4 under a high efficiency of 97%at the optimum load conditions of 10kΩ.Strong electric field gradient at the output circuit is applicable for the electrical discharge generation.