A new and rapid process for production of solution-derived (Pb, La)(Zr, Ti)O₃ thin films and powders

A simple and rapid process for synthesizing (Pb, La)(Zr, Ti)O₃ (PZT, PLZT, and PLT) precursor solutions has been developed. This process, termed the "basic route to PLZT" (or BRP) process, offers several advantages over standard methods, including rapid solution synthesis (<10 min), use of commercially available materials, film production under ambient conditions, ease of lanthanum dissolution at high concentrations (<1 min), and no heating requirements during solution synthesis. The PLZT precursor solution synthesis involves dissolution of lead acetate (or acetyl acetate) in pyridine followed by addition of a pre-dissolved mixture of titanium and zirconium iso-propoxide in toluene. The lanthanum source can then be added and, depending on the precursor, total synthesis time was <10 min. The preferred lanthanum starting material is a highly soluble bis(isopropyl)aryloxide complex; however, this compound is extremely air and water sensitive. The compositions investigated in this study include PZT 40/60, PLZT 3/30/70, 5/30/70, and 10/40/60, and PLT films with 10-20 mol% La. All films were crystallized at 650°C and exhibit ferroelectric properties comparable to films produced by other techniques which require higher crystallization temperatures.