Ferroelectrics for Tunable High-Power Applications

This paper presents recent development of ferroelectric varactors for tuning applications. While Barium-StrontiumTitanate (BST) based thick-film components have formerly been realized in planar interdigital (IDC) topology, low-sintering BST composites offer the possibility of metal-insulator-metal (MIM) structures. The possibilities and limits of this technology are discussed in respect to high-power applications, especially the power handling capability and linearity are considered. Thick-film components with very high power rating of 1kW show acoustic effects, which have to be carefully considered in the design.