In the last few decades the applications of piezoelectrics to sensors have witnessed a dramatic acceleration and new devices and materials have been discovered. Some of the highlights include electrostrictive materials for positioners, relaxor-normal ferroelectric single crystals with very high electromechanical couplings for medical transducers, thin/thick PZT films for microelectromechanical systems, starting from a sophisticated chemical technology, and multilayer actuators fabricated by a cofiring technique. All will make a remarkable industrial impact in the 21st century.

Zusammenfassung
Proceedings of the NATO Advanced Research Workshop, Predeal, Romania, 24-27 May, 1999

Inhalt
I Fundamentals on Ferroelectrics Piezoelectrics and Relaxors.- Piezo-, pyro- and ferroelectricity in biological materials.- Piezo-, pyro- and ferroelectric polymers.- The kinetic and scattering of nonequilibrium phonons by domain walls and grain boundaries in monocrystal and ceramics of BaTiO3.- Ferroelectrics with periodically layered domain structure: computer simulation of acoustical properties.- Structure and properties of novel Pb(B'1/2 Nb1/2)O3-PbTiO3 binary systems with high piezoelectric coupling.- Nano-size ferroelectric structures.- Influence of Bi and Y additions on the electromechanical anisotropy of lead titanate ceramics.- Bi4Ti3O12-Based piezoelectric ceramics for high temperature applications.- II Powder Preparation and Processing.- Influence of processing parameters on the properties of PZT materials.- Smart structures by integrated piezoelectric thin fibers.- Hydrothermal synthesis and processing of undoped and doped BaTiO3 fine particles.- Chemical processing of PbTiO3/Organic hybrid and Pb(Zr,Ti)O3 thick films.- Preparation and characterization of thick piezoelectric films on alumina substrates.- III Microstructural and Piezoelectric Characterisation.- Nonlinear piezoelectric response in ferroelectric ceramics.- Influence of microstructure on microscopic and macroscopic strain behavior of soft PZT ceramics.- The effect of static compressive stress on the high field dielectric properties of hard PZT ceramics.- Stress dependence of the piezoelectric, dielectric and elastic properties of PZT ceramics.- Switching of ferroelectric nanostructures.- Measurement and simulation of the electromechanical behaviour of piezoelectric stack transducers.- 0.9PMN-0.1PT ceramics: from electromechanical properties to applications via nanostructural characterization.-Solid-state 25Mg, 45Sc and 93Nb MAS NMR studies: local B-site chemical environments and ordering in Pb(Mg1/3Nb2/3)O3(PMN) and related relaxor ferroelectrics.- Piezoelectric properties of proton-exchanged optical waveguides.- A novel tool for experimental analysis of surface phenomena.- The influence of the material constants and mass-loading on coupling coefficient of monolithic filters.- IV Processing And Characterisation of Films.- Thick and composite piezoelectric coatings for biomedical and high temperature ultrasound.- Pulsed-laser deposition and characterization of thin films.- Correlated compositional, morphological and electrical characterization of PLD piezoelectric thin films.- Piezoelectric thin films for high frequency electroacoustic devices.- Photoelectric and dielectric spectroscopy study of PZT thin film electronic structure.- The influence of interface on the spontaneous polarisation in PbTiO3 thin films deposited on a silicon substrate.- V Applications of Bulk Devices and Thin Films.- Compact piezoelectric ultrasonic motors.- Piezoelectric actuators using ultrasonic waves.- MEMS application of piezoelectric materials.- Fabrication and modeling of miniaturized piezoelectric transducers for imaging applications.- Flextensional composite transducers: designing, fabrication and application.- A disk type piezoelectric transformer with crescent shape input electrodes.- Design and performance of a linear piezoelectric wedgeworm actuator.- Piezoelectric components for technical applications.- Author Index.