Use of Stress To Produce Highly Oriented Tetragonal Lead Zirconate Titanate (PZT 40/60) Thin Films and Resulting Electrical Properties

Abstract

Thin films of Pb(Zr 0.4 Ti O.6 )O 3 produced by chemical solution deposition were used to study the effects of stress from different platinized single-crystal substrates on film orientation and resulting electrical properties. Films deposited on MgO preferred a (001) orientation due to compressive stress on the film during cooling through the Curie temperature (T C ). Films on Al 2 O 3 were under minimal stress at T C , resulting in a mixture of orientations. Those on Si preferred a (111) orientation due to templating from the bottom electrode. Films oriented in the ͗001͘ direction demonstrated lower dielectric constants and higher P r and ؊d 31 values than (111) films. S. E. Trolier-McKinstry-contributing editor Manuscript No. 10468.

Pyroelectric response of lead zirconate titanate thin films on silicon: Effect of thermal stresses

“…We note that experimentally PZT films on Si substrates contain polydomain microstructures that form so as to relax thermal stresses due to the TEC mismatch and the transformational stresses due to the FE-PE phase transformation at T C . [59][60][61][62][63][64][65][66] Several studies have been reported which provide a rigorous analysis of polydomain heterostructures in epitaxial FEs taking into account these (volumetric) sources of internal stresses as well as localized strain fields near defects using thermodynamic models and phase-field approaches. 20,55,67,68 Therefore, to describe the experimental observations, more sophisticated models need to be developed to describe the effect of grain and domain boundaries, grain texture, and the extrinsic contribution to the pyroelectric coefficient resulting from reversible domain wall motion.…”

{001} Oriented piezoelectric films prepared by chemical solution deposition on Ni foils

“…The hypothesis was that the comparatively larger thermal expansion coefficient of Ni, relative to Si, and the small thickness of the foil substrate, would facilitate ferroelastic domain wall motion relative to films on Si. 13 Out-of-plane polarization in PZT films should yield large remanent polarizations and low dielectric permittivities as compared with PZT films on Si, which have a significant fraction of polarization which lies in-plane. 13 …”

“…13 Out-of-plane polarization in PZT films should yield large remanent polarizations and low dielectric permittivities as compared with PZT films on Si, which have a significant fraction of polarization which lies in-plane. 13 …”

Sol–gel derived Pb(Zr,Ti)O3 thin films: Residual stress and electrical properties

“…22 Furthermore, reports indicate that the stress state upon cooling through the Curie temperature can affect the domain configuration, and thus dielectric properties, in tetragonal PZT thin films. 23 A tensile stress on cooling from the cubic state yields a preferred orientation of the c-axis in the plane of the substrate, whereas a compressive stress would form the c-direction normal to the substrate. The composition in the present study (i.e., 53/47) was on the rhombohedral/tetragonal phase boundary, and preferred orientation of domains could not be substantiated by XRD or SEM.…”