Oriented lead germanate thin films by excimer laser ablation

Abstract

c-axis-oriented lead germanate thin films were fabricated, to our knowledge for the first time, by pulsed excimer laser ablation. Composition analysis indicated that the films are stoichiometric and very close to the target composition. The orientation of the films along the unique polar axis (c axis) appeared to have been influenced by the ablation fluence via the energy of the ablated species and by the nature of substrates. Films were found to be ferroelectric at room temperature, with a remanent polarization of about 2.5 µ C/cm² at a coercive field of 55 kV/cm. The (003)-oriented films also showed a clear onset of ferro-paraelectric phase transition at about 175° C close to that of single crystals.