Effect of Zr Substitution for Ti on BaZrxTi1−XO3 Thin Films for Energy Storage Applications

Abstract

Recently, energy storage capacitors research attention turned towards lead-free and eco-friendly dielectric BaTiO3. Many efforts have been made to improve the dielectric properties of the BTO thin film capacitors. Barium titanate is one of the most studied ferroelectric materials because they possess high permittivity, polarization and piezoelectric properties, low dielectric loss and high dielectric breakdown field and it is very attractive for many applications. With this motivation, highly oriented thin films of BaZrxTi1−xO3 (BZT) with different concentrations of Zr were fabricated on LSMO/MgO(100) substrates to compare their energy storage performances while varying Zr concentration in Pt/BZT/LSMO/MgO(100) heterostructures. Deposition of BZT layers were done at an oxygen partial pressure of ∼150 mTorr. During laser ablation of BZT at a laser energy 250 mJ on the target, substrate temperature was maintained at 650 °C using an excimer laser operating at a pulse frequency of 10 Hz. Thickness of the thin films was precisely maintained by controlling the number of laser shots. These thin films was analyzed by x-ray diffractometry and Raman spectroscopy. Studies on structural phase transition, ferroelectric, dielectric, leakage current, and energy-storage properties revealed the applicability of these thin film structures in future integrated high energy density capacitors. We will present the aforementioned properties of these thin films and will discuss the intended energy storage applications of this dielectric material in detail.