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Improvements of the d(sub 33) co-efficient for thick-film lead zirconate titanate (PZT) layers are detailed. The combination of small and large particles does increase the d(sub 33) of the film and justifies the investigation and it is shown that the consistency of the results can be increased in comparison to the ball milled devices, although they are not as consistent as the attritor3 devices.

A multi-degree-of-freedom (MDOF) ultrasonic motor is described. It has few parts and relies on inexpensive thick-film technology.

This paper presents the modeling and optimization of an electromagnetic-based generator for generating power from ambient vibrations. Basic equations describing such generators are presented and the conditions for maximum power generation are described. Two-centimeter scale prototype generators, which consist of magnets suspended on a beam vibrating relative to a coil, have been built and tested. The measured power and modeled results are compared. It is shown that the experimental results confirm the optimization theory. Index Terms--Displacement, energy conversion, generators and resonance.

The theory, design and simulation of electromagnetic micropower generators with electroplated micromagnets fabricated using standard microelectromechanical system processing techniques are discussed. The voltage and power that can be generated from different designs are determined using electromagnetic two-dimensional finite element analysis simulations.

The optimum mode of double-ended tuning-fork-style resonators is a lateral vibration in the plane of the wafer. Lateral vibrations are typically excited using the comb drive approach, but this requires modification to the resonator structure. This paper reports a simple method for exciting and detecting lateral vibrations without modifying the resonator, thereby enabling the optimum dynamically balanced structure to be used. This approach uses plane electrodes positioned parallel to the resonator's tines to excite the vibrations while the change in resistance along the length of the resonator enables the vibrations to be detected. Test devices have been fabricated in single-crystal silicon using the buried oxide in silicon-on-insulator wafers as a sacrificial layer. The resonators are 340-[micro]m long, 3- [micro] m thick with tines 2-[micro]m wide. The gap between the tines and the electrode is 2 [micro] m. Visual inspection in a scanning electron microscope and electrical tests have confirmed the validity of this approach. [475]