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The stability and magnitude of photovoltage response in (Pb0.97La0.03)(Zr0.52Ti0.4g)O_3 (PLZT) ferroelectric thin films were investigated in the present work. Photovoltage degrading in multi-cycle ultraviolet (UV) light illumination was observed in Au/PLZT/Pt sandwich capacitor configuration and in-plane polarized configuration with a pair of top Au interdigital electrodes. For the in-plane polarized configuration, which had a greatly enhanced electrode gap, the reduction ratio of photovoltage during multi-cycle UV illumination was significantly smaller hence the stability of photovoltage was greatly improved over the sandwich capacitor configuration. Trapping of photo-induced charges and polarization screening at the ferroelectric-electrode interfaces were found to be the major cause for the degrading of photovoltage in ferroelectric films. Furthermore, for the Au/PLZT/Pt capacitor, the magnitude and even the polarity of the photovoltage were remarkably affected by the asymmetric interfacial Schottky barriers due to the small photovoltage magnitude determined by the small film thickness. [ABSTRACT FROM AUTHOR]

Photovoltaic effect in ferroelectric materials exhibits potential for applications of sensors and remote controls in micro-electro-mechanical systems, and a systematic evaluation on the photovoltaic behavior in ferroelectric materials becomes important. However, as a critical parameter that determines the photovoltaic output in ferroelectric thin films, the film thickness effect on photocurrent output has not been investigated for thin film samples. In this work, a theoretical model has been developed to describe the thickness-dependent photocurrent in (Pb0.97La0.03)(Zr0.52Ti0.48)O3(PLZT) thin films with a sandwich electrode structure. This model indicates that photocurrent increases exponentially with the decrease in film thickness. Therefore, a significantly enhanced photocurrent can be expected in thinner PLZT films. The predicted thickness dependence of the short circuit photocurrent was also supported by our experimental results. [ABSTRACT FROM AUTHOR]

The micromachined gyroscope is rapidly gaining popularity as a rate sensor for application in areas such as automotive and aerospace systems, where low power consumption, high sensitivity, low temperature drift and good stability are prerequisites. In this paper, the overall design and fabrication process of a reactive ion-etched inertial resonant gyroscope based on the capacitive sensing principle is reported. The experimental results are also discussed. [ABSTRACT FROM AUTHOR]

Proposes a quasi-resonant PWM converter topology for unity power factor application. Achievement of zero-voltage transition conditions for both the main and auxiliary switching devices; Clamping of the blocking voltage at a relatively low level during off period; Analysis of the operating modes of the converter.