Ultralow temperature processing and integration of dielectric resonators on silicon substrates for system-on-chip applications

Ultralow temperature processing of Ba2Ti9O20 thin-film ceramics and the attachment of a porous dielectric resonator cylinder on a conducting prepatterned silicon substrate have been accomplished using a hydrothermal process at 150 degrees C/3 h. Enhanced densification and mechanical strength at the bulk ceramic-thin-film interface were induced by a dissolution-crystallization process involving a sol-gel solution under 13-15 atm pressure. Recrystallization forms electrical bridges between powder particles to form an interconnected microstructure, which eliminates grain boundary-defects and, hence, improves the dielectric properties. This method has potential for growth of dielectric resonators on integrated circuits for system-on-chip applications and is implemented for the fabrication of an integrated dielectric resonator antenna.