Thin-film decoupling capacitors for multichip modules

Thin-film decoupling capacitors based on ferroelectric lead lanthanum zirconate titanate (PLZT) films are being developed for use in advanced packages, such as multichip modules. These thin-film decoupling capacitors are intended to replace multilayer ceramic capacitors for certain applications, since they can be more fully integrated into the packaging architecture. The increased integration that can be achieved should lead to decreased package volume and improved highspeed performance, due to a decrease in interconnect inductance. PLZT films are fabricated by spin coating using metal carboxylate/alkoxide solutions. These films exhibit very high dielectric constants (/spl epsiv//spl ges/900), low dielectric losses (tan /spl delta//spl ap/0.01), excellent insulation resistances (/spl rho/>10/sup 13/ /spl Omega/-cm at 125/spl deg/C), and good breakdown field strengths (E/sub B//spl ap/900 kV/cm). For integrated circuit applications, the PLZT dielectric is less than 1 /spl mu/m thick, which results in a large capacitance/area (8-9 nF/mm/sup 2/). The thin-film geometry and processing conditions also make these capacitors suitable for direct incorporation onto integrated circuits and for packages that require embedded components.>