title: Strongly Enhanced Piezoelectric Response in Lead Zirconate Titanate Films with Vertically Aligned Columnar Grains.
abstract: Pb(Zr0.52Ti0.48)O3(PZT) films with (001) orientation were deposited on Pt(111)/Ti/SiO2/Si(100) substrates using pulsed laser deposition. Variation of the laser pulse rate during the deposition of the PZT films was found to play a key role in the control of the microstructure and to change strongly the piezoelectric response of the thin film. The film deposited at low pulse rate has a denser columnar microstructure, which improves the transverse piezoelectric coefficient (d31f) and ferroelectric remanent polarization (Pr), whereas the less densely packed columnar grains in the film deposited at high pulse rates give rise to a significantly higher longitudinal piezoelectric coefficient (d33f) value. The effect of film thickness on the ferroelectric and piezoelectric properties of the PZT films was also investigated. With increasing film thickness, the grain column diameter gradually increases, and also the average Prand d33fvalues become larger. The largest piezoelectric coefficient of d33f= 408 pm V-1was found for a 4-μm film thickness. From a series of films in the thickness range 0.5-5 μm, the z-position dependence of the piezoelectric coefficient could be deduced. A local maximum value of 600 pm V-1was deduced in the 3.5-4.5 μm section of the thickest films. The dependence of the film properties on film thickness is attributed to the decreasing effect of the clamping constraint imposed by the substrate and the increasing spatial separation between the grains with increasing film thickness.
authors.affiliation: MESA+ Institute for Nanotechnology, University of Twente , P.O. Box 217, Enschede 7500AE, The Netherlands.|Solmates B.V. , Drienerlolaan 5, Enschede 7522NB, The Netherlands.|International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology , Hanoi 10000, Vietnam.
authors.forename: Minh D
authors.identifier: http://orcid.org/0000-0001-9725-4004
authors.initials: MD
authors.lastname: Nguyen
authors.affiliation: MESA+ Institute for Nanotechnology, University of Twente , P.O. Box 217, Enschede 7500AE, The Netherlands.
authors.forename: Evert P
authors.initials: EP
authors.lastname: Houwman
authors.affiliation: Solmates B.V. , Drienerlolaan 5, Enschede 7522NB, The Netherlands.
authors.forename: Matthijn
authors.initials: M
authors.lastname: Dekkers
authors.affiliation: MESA+ Institute for Nanotechnology, University of Twente , P.O. Box 217, Enschede 7500AE, The Netherlands.
authors.forename: Guus
authors.initials: G
authors.lastname: Rijnders
keywords: PZT film; microstructure; piezoelectric response; pulsed laser deposition; vertically aligned columnar growth