Polarization reversal and high dielectric permittivity in lead magnesium niobate titanate thin films

Ferroelectric thin films of the morphotropic phase boundary composition in the lead magnesium niobate-lead titanate solid solution system were fabricated through the sol-gel spin-on technique. The rapid thermally annealed films showed a very high dielectric constant of 2900, with a concomitant low dissipation factor of 0.02; the films were hysteretic with a saturation remanence of 11 μC/cm2 and a coercive voltage of 0.5 V. The storage charge density observed at 5 V was 210 fC/μm2. These films merit consideration for potential application in ferroelectric nonvolatile random access memories (NVRAMs), and in high bit density metal-oxide-semiconductor (MOS) dynamic random access memories (DRAMs).