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

Abstract

Flexible metal foil substrates are useful in some microelectromechanical systems applications including wearable piezoelectric sensors or energy harvesters based on Pb(Zr,Ti)O3 (PZT) thin films. Full utilization of the potential of piezoelectrics on metal foils requires control of the film crystallographic texture. In this study, {001} oriented PZT thin films were grown by chemical solution deposition (CSD) on Ni foil and Si substrates. Ni foils were passivated using HfO2 grown by atomic layer deposition in order to suppress substrate oxidation during subsequent thermal treatment. To obtain the desired orientation of PZT film, strongly (100) oriented LaNiO3 films were integrated by CSD on the HfO2 coated substrates. A high level of {001} LaNiO3 and PZT film orientation were confirmed by X-ray diffraction patterns. Before poling, the low field dielectric permittivity and loss tangents of (001) oriented PZT films on Ni are near 780 and 0.04 at 1 kHz; the permittivity drops significantly on poling due to in-plane to out-of-plane domain switching. (001) oriented PZT film on Ni displayed a well-saturated hysteresis loop with a large remanent polarization ∼36 μC/cm2, while (100) oriented PZT on Si showed slanted P-E hysteresis loops with much lower remanent polarizations. The |e31,f| piezoelectric coefficient was around 10.6 C/m2 for hot-poled (001) oriented PZT film on Ni.

Polar-axis-oriented crystal growth of tetragonal PZT films on stainless steel substrate using pseudo-perovskite nanosheet buffer layer

“…Stacking buffer layers with perovskite-type lattice surfaces is a prospective approach to achieve the crystal orientation of PZT films on versatile substrates. Some researchers have reported successful results (e.g., using CeO 2 /YSZ or SrTiO 3 buffer layers, 4,7,12 or one-axis-oriented (100)LaNiO 3 template 13,14 ) in which the preferential c-/a-domain formation was realized together with the variation of their ferroelectric/piezoelectric properties. Single-crystal nanosheets of calcium niobate (Ca 2 Nb 3 O 10 ) that possess a pseudo-perovskite-type crystal structure 15,16 are currently being utilized for the buffer layers to control the crystal orientation of perovskite-or layer-perovskite-type dielectric films (SrTiO 3 21 etc.)…”

“…14 The films deposition of ferroelectric / piezoelectric materials on flexible metal substrates would greatly contribute to advanced MEMS application, such as dynamic actuators, high-sensitive sensors or high-efficiency energy harvester, because of flexibility, elasticity and fracture toughness of the substrates. The ns-CN layer will possess some unique advantages for the crystal orientation of PZT films because of its negligible layer thickness (= several nanometers) and the solubility of Ca and Nb components into PZT layer.…”

A flexible, high-performance magnetoelectric heterostructure of (001) oriented Pb(Zr0.52Ti0.48)O3film grown on Ni foil

“…[24][25][26][27] The large c-domain population in the PZT film on Ni could be due to a combination of the compressive stress induced by the thermal expansion mismatch between PZT and Ni and the relaxation of stress by bending of the thin foil structure. 4,5,22,29 The ME response of the PZT/Ni composite corona poled at different DC voltages is shown in Fig. 3(c).…”

“…The low cost of these foils, coupled with their ready availability, makes them particularly useful in the development of embedded capacitors, energy harvesting devices, and wearable electronics. [1][2][3][4][5] Advantages of these foils include the possibility of large area fabrication and on demand design adaptivity. Additionally, their high fracture strength provides a superior alternative to brittle, rigid Si substrates when they are stressed by large deformations and impacts.…”

“…The in-plane dimensions of the sample are 21.5 × 6.5 mm 2 . The PZT/Ni sample was prepared following the procedure described elsewhere 4 and in the supplementary material. A 1.5 µm-thick PZT film was deposited on a 25 µm-thick, Ni (Alfa Aesar, 99.99%) foil.…”