Tailoring the composition of lead zirconate titanate by atomic layer deposition

The incubation time during atomic layer deposition (ALD) of lead oxide, zirconium oxide, and titanium oxide on each other was quantified in order to precisely control the composition of lead zirconate titanate (PZT). The desired stoichiometry of Pb:Zr:Ti=2:1:1, which yields the desired ferroelectricity, was found to depend strongly on the ALD sequence, the substrate of choice, as well as the postdeposition annealing temperature. With the desired stoichiometry, the ferroelectric and piezoelectric properties of the PZT films were validated by polarization–voltage hysteresis loop and piezoresponse force microscopy, respectively, demonstrating that ALD method is a viable technique for ultra thin ferroelectric films for device applications.