Ceramic dielectric film capacitors fabricated on aluminum foils by chemical solution deposition

Integration of oxides onto base metal substrates offers great advantages in cost and weight reduction, device miniaturization, and flexibility in packaging. In this work, we report the deposition of dielectric Pb0.92La0.08Zr0.52Ti0.48O3−δ (PLZT 8/52/48) films on aluminum foils by an in-air crystallization process. Film-on-foil structures with and without conductive oxide LaNiO3 (LNO) buffer layer between PLZT film and aluminum foil were tested. Utilization of LNO buffer layer dramatically improved the dielectric and ferroelectric properties of the overlying PLZT compared with those for films deposited directly on aluminum. The improvements in electrical properties were attributed to the suppression of cubic non-ferroelectric layer at the metal/dielectric interface by LNO buffer layer. This work can be extended to the integration of other functional oxide materials with light, conductive, and inexpensive aluminum substrates for a broad range of applications.