Synthesis and Electrical Characterization of Thin Films of PT and PZT Made from a Diol‐Based Sol‐Gel Route

Lead titanate (PT) sols were prepared using propanediol, butanediol, or pentanediol solutions of lead acetate trihydrate and titanium diisopropoxide bis(acetylacetonate). Precursor sols for PbZr 0.53 Ti 0.47 O 3 (PZT) films were prepared from propanediol solutions, with zirconium tetrapropoxide being used as the zirconium source. Films were formed by spin‐coating the sols onto silicon and platinized silicon substrates; the resulting gel layers were converted to ceramic films by adopting a two‐stage heating schedule with final firing temperatures of 600–700°C. Information on film crystallization, microstructure development, and electrical properties is presented for both compositions. The limiting thickness of surface‐smooth crack‐free single‐layer films was ∼1 μm. The PT films exhibited a “linear” polarization‐electric field ( P‐E ) response, while the PZT films gave rise to characteristic ferroelectric P‐E hysteresis loops. A 0.5 μm thick single‐layer PZT film exhibited remanent polarization (P r ) values of ∼34 μC·Cm −2 , with a coercive field ( E c ) of ∼45 kV·Cm −2 ; the relative permittivity (ɛ r ) and the dissipation factor ( D ) were ∼1250 and 0.07. For a 1 μm single‐layer PZT film, the respective values were P r ∼19 μC∼Cm −2 , E c ∼40 kV∼Cm −2 , ɛ r ∼750, and D = 0.03.