Canonical Correlation Analysis

Abstract

© 2006 by Nova Science Publishers, Inc. All rights reserved. High dielectric tenability, low dielectric loss tangent and appropriate dielectric constant, are basic requirements for microwave device applications, such as tunable oscillators, phase shifters and varactors. Ferroelectric materials, for example, barium strontium titanate (Ba1-xSrxTiO3or BST), are known to be the most promising candidates for such applications. A critical issue for practical device application of ferroelectric materials is the reduction of the dielectric losses, because the dielectric loss tangents of BST ferroelectric materials are relatively high. Recently, many efforts have been made in order to reduce the dielectric losses of BST based ferroelectrics. It has been found that doping of oxides, such as MgO, ZrO2and Al2O3, TiO2, LaAlO3, and Bi15ZnNb15O7and so on, with low dielectric losses into ferroelectric materials is an effective way to reduce the dielectric losses. In addition to the reduction in dielectric losses, the introduction of oxides would also be able to modify the dielectric constant to be suitable for practical applications. We will review the recent progress in tunable properties of ferroelectrics modified for microwave device applications.