LTCC glass-ceramic composites for microwave application

Advanced materials of rare earth derived glass-and reactive bonded glass-ce ramic composites are exceptionally interesting for IC packaging, radar, ant ennas and wireless technologies for the next generation of miniature electr onic devices. Glass-ceramic composites in the system 1:1:4 BaO-Nd2O3-TiO2 a nd modified rare earth glasses based on boron oxide for passive integration in LTCC demonstrate excellent dielectric properties in the middle permitti vity epsilon range of 20-70 with high quality factor Q and low temperature coefficient TCf at microwave frequencies. Depending on the glass-ceramic sy stem, concentration, significant processing parameters e.g. powder preparat ion techniques and sintering of dense composite at temperatures < 900 degre esC were achieved. Dielectric properties were studied by a cavity resonator method at frequencies 1-6 GHz in correlation of the crystalline microstruc ture. This work was supported by tridimensional modeling systems to estimat e dielectric behavior of multiphase glass-ceramic composites. (C) 2001 Else vier Science Ltd.