Multilayer Piezoelectric Research Articles

Modeling and Characterization of Multilayer Piezoelectric Stacks via Dynamic Stiffness Method

Multilayer piezoelectric stacks, which are multiple layers of piezoelectric materials placed on top of each other, are widely used to achieve precise linear movement and high-force generation. In this paper, a dynamic stiffness (DS) method for the dynamic vibration analysis of multilayer piezoelectric stacks is presented. First, the general solutions for all physical quantities of the three vibration contributions (i.e., pure vibration, symmetrically coupled vibration, and anti-symmetrically coupled vibration) are derived from the governing equations of motion. Then, the DS matrices of each layer of the piezoelectric stack are obtained, and they are assembled to form a global DS matrix. The electrical impedances and the mode shapes of a piezoelectric stack consisting of two piezoelectric disks connected in series and in parallel are calculated using our method as well as by the finite element method. The comparison shows good agreement. Finally, the effect of the number of layers on the dynamic responses of piezoelectric stacks is investigated. The DS method developed here provides an efficient and accurate analytical tool for the parametric and optimization analysis of the coupled vibrations of multilayer piezoelectric structures.

Structural Design and Experimental Studies of Resonant Fiber Optic Scanner Driven by Co-Fired Multilayer Piezoelectric Ceramics.

Piezo-driven resonant fiber optic scanners are gaining more and more attention due to their simple structure, weak electromagnetic radiation, and non-friction loss. Conventional piezo-driven resonant fiber optic scanners typically use quadrature piezoelectric tubes (piezo tubes) operating in 31-mode with high drive voltage and low excitation efficiency. In order to solve the abovementioned problem, a resonant fiber scanner driven by co-fired multilayer piezoelectric ceramics (CMPCs) is proposed in which four CMPCs drive a cantilevered fiber optic in the first-order bending mode to achieve efficient and fast space-filling scanning. In this paper, the cantilever beam vibration model with base displacement excitation was derived to provide a theoretical basis for the design of the fiber optic scanner. The finite element method was used to guide the dynamic design of the scanner. Finally, the dynamics characteristics and scanning trajectory of the prepared scanner prototype were tested and compared with the theoretical and simulation calculation results. Experimental results showed that the scanner can achieve three types of space-filling scanning: spiral, Lissajous, and propeller. Compared with the structure using piezo tubes, the designed scanner achieved the same scanning range with smaller axial dimensions, lower drive voltage, and higher efficiency. The scanner can achieve a free end displacement of 10 mm in both horizontal and vertical directions under a sinusoidal excitation signal of 50 Vp-p and 200 Hz. The theoretical, simulation and experimental results validate the feasibility of the proposed scanner structure and provide new ideas for the design of resonant fiber optic scanners.

Influence of AlN/ScAlN piezoelectric multilayer on the electromechanical coupling of FBAR

Based on the truth, the electromechanical coupling in the top and bottom Mo electrodes caped AlN can be enhanced by replacing the Sc doped AlN (ScAlN). We tune the electromechanical coupling (kt2) of the film bulk acoustic resonator (FBAR) by varying the thickness ratio in AlN and ScAlN piezoelectric multilayer. We found that the electromechanical coupling of the piezoelectric-multilayer FBAR is area size dependent. In order to investigate the multilayer electromechanical coupling in various thickness ratios, we propose a theory to simulate both materials piezoelectric constants e varying with the area size. In various thickness ratios, the effective piezoelectric constant of the AlN layer increases with the area of FBAR, but the ScAlN layer exhibits an optimal piezoelectric constant in increasing area. Eventually, we realized that increasing the significant piezoelectric constant is inevitable for reducing the size of FBARs.

Printed Multilayer Piezoelectric Transducers on Paper for Haptic Feedback and Dual Touch-Sound Sensation.

With a growing number of electronic devices surrounding our daily life, it becomes increasingly important to create solutions for clear and simple communication and interaction at the human machine interface (HMI). Haptic feedback solutions play an important role as they give a clear direct link and response to the user. This work demonstrates multifunctional haptic feedback devices based on fully printed piezoelectric transducers realized with functional polymers on thin paper substrate. The devices are flexible; lightweight and show very high out-of-plane deflection of 213 µm at a moderate driving voltage of 50 Vrms (root mean square) achieved by an innovative multilayer design with up to five individually controllable active layers. The device creates a very clear haptic sensation to the human skin with a blocking force of 0.6 N at the resonance frequency of 320 Hz, which is located in the most sensitive range of the human fingertip. Additionally the transducer generates audible information above two kilohertz with a remarkable high sound pressure level. Thus the paper-based approach can be used for interactive displays in combination with touch sensation; sound and color prints. The work gives insights into the manufacturing process; the electrical characteristics; and an in-depth analysis of the 3D deflection of the device under variable conditions

Resonant Magnetoelectric Effect at Low Frequencies in Layered Polymeric Cantilevers Containing a Magnetoactive Elastomer

In this work, the resonance enhancement of magnetoelectric (ME) coupling at the two lowest bending resonance frequencies was investigated in layered cantilever structures comprising a magnetoactive elastomer (MAE) slab and a commercially available piezoelectric polymer multilayer. A cantilever was fixed at one end in the horizontal plane and the magnetic field was applied horizontally. Five composite structures, each containing an MAE layer of different thicknesses from 0.85 to 4 mm, were fabricated. The fundamental bending resonance frequency in the absence of a magnetic field varied between roughly 23 and 55 Hz. It decreased with the increasing thickness of the MAE layer, which was explained by a simple theory. The largest ME voltage coefficient of about 7.85 V/A was measured in a sample where the thickness of the MAE layer was ≈2 mm. A significant increase in the bending resonance frequencies in the applied DC magnetic field of 240 kA/m up to 200% was observed. The results were compared with alternative designs for layered multiferroic structures. Directions for future research were also discussed.

Design and Development of Outstanding Strain Properties in NBT-Based Lead-Free Piezoelectric Multilayer Actuators by Grain-Orientation Engineering

Design and Development of Outstanding Strain Properties in NBT-Based Lead-Free Piezoelectric Multilayer Actuators by Grain-Orientation Engineering

Application of Multilayer Piezoelectric Actuator in Lithography Scanners

Application of Multilayer Piezoelectric Actuator in Lithography Scanners

Erratum to “Characterization of Multilayer Piezoelectric Stacks Down to 100K” [2022 65-82

Erratum to “Characterization of Multilayer Piezoelectric Stacks Down to 100K” [2022 65-82

Characterization of Multilayer Piezoelectric Stacks Down to 100K

Characterization of Multilayer Piezoelectric Stacks Down to 100K

Magnetoelectric Response of Laminated Cantilevers Comprising a Magnetoactive Elastomer and a Piezoelectric Polymer, in Pulsed Uniform Magnetic Fields.

The voltage response to pulsed uniform magnetic fields and the accompanying bending deformations of laminated cantilever structures are investigated experimentally in detail. The structures comprise a magnetoactive elastomer (MAE) slab and a commercially available piezoelectric polymer multilayer. The magnetic field is applied vertically and the laminated structures are customarily fixed in the horizontal plane or, alternatively, slightly tilted upwards or downwards. Six different MAE compositions incorporating three concentrations of carbonyl iron particles (70 wt%, 75 wt% and 80 wt%) and two elastomer matrices of different stiffness are used. The dependences of the generated voltage and the cantilever’s deflection on the composition of the MAE layer and its thickness are obtained. The appearance of the voltage between the electrodes of a piezoelectric material upon application of a magnetic field is considered as a manifestation of the direct magnetoelectric (ME) effect in a composite laminated structure. The ME voltage response increases with the increasing total quantity of the soft-magnetic filler in the MAE layer. The relationship between the generated voltage and the cantilever’s deflection is established. The highest observed peak voltage around 5.5 V is about 8.5-fold higher than previously reported values. The quasi-static ME voltage coefficient for this type of ME heterostructures is about 50 V/A in the magnetic field of ≈100 kA/m, obtained for the first time. The results could be useful for the development of magnetic field sensors and energy harvesting devices relying on these novel polymer composites.

Concave Array Ultrasonic Transducer From Multilayer Piezoelectric Ceramic for Photoacoustic Imaging.

Implementation of piezoelectric multilayer ceramic (MLC) is an effective way to reduce impedance and improve the performance of linear-array transducer for ultrasonic system applications. However, the ultrasonic image derived from a planar linear-array transducer generally suffers from degradation of lateral resolution and contrast. In this article, we designed and fabricated a focused 5-MHz 128-element linear-array ultrasonic transducer with concave structure using five-layered 0.1Pb (Ni1/3Nb2/3)O3 -0.35Pb(Zn1/3Nb2/3)O3 -0.15Pb(Mg1/3Nb2/3)O3-0.1PbZrO3-0.3PbTiO3 (PNN-PZN-PMN-PZ-PT) piezo- electric ceramic. The transducer showed a bandwidth of 63% at -6 dB and the lateral resolution up to 0.33 mm. An improved transmission signal of 90% higher than a commercial single-layer ceramic transducer was also achieved. We further demonstrated high-resolution photoacoustic imaging with the obtained concave linear-array transducer.

Ultrasonic Transducer From Piezoelectric Polymer Multilayer Through Electrophoretic Deposition for Photoacoustic Imaging.

Emerging ultrasound imaging modality based on optical-generated acoustic waves, such as photoacoustic (PA) imaging, has enabled novel functional imaging on biological samples. The performance of the ultrasonic transducer plays a critical role in producing higher quality PA images. However, the high electrical impedance of the small piezoelectric elements in the transducer array causes an electrical mismatch with external circuitry and results in degraded sensitivity. One effective method for reducing the electrical impedance is to implement a piezoelectric multilayer configuration instead of the conventional single layer for the transducer. In this work, we introduced an ultrasonic transducer comprising a piezoelectric polymer multilayer structure produced by an innovative multicycle powder-based electrophoretic deposition, using a suspension of polymer nanoparticles. The multicycle electrophoretic deposition overcomes the redissolution issue in solution-based methods. The ultrasonic transducer comprising the piezoelectric polymer multilayer exhibits significantly enhanced receiving sensitivity as compared to the ultrasonic transducer using a single layer. Ultrasonic transducer with multielement array configuration is obtained using the piezoelectric polymer multilayer, and PA imaging with improved resolution is demonstrated. Theoretical analysis shows that the enhanced transducer performance is mainly attributed to the improved electrical impedance match between the piezoelectric polymer element in the transducer and external receiving circuit.

Rigidity of a Multilayer Piezoelectric Actuator for the Nano and Micro Range

The rigidity and elastic pliability of a multilayer piezoelectric actuator for the nano and micro range is investigated. Its mechanical and control characteristics are determined. The rigidity and elastic pliability are considered for different types of control.

Lead Free Multilayer Piezoelectric Actuators by Economically New Approach

The replacement of lead zirconate titanate ceramics (PZTs), with a lead-oxide (PbO)-free alternative is the subject of intense investigation worldwide. In this research, a cheap reliable methodology for the fabrication of multilayers (MLs) of lead-free potassium sodium niobate (KNN)-based ceramics is presented without the need for vacuuming and/or hot isostatic pressing of the tape. The thickness per active layer was 193 μm and 102 μm for the 10 and 16 layer MLs actuators, respectively. Effective d33 (piezoelectric coefficient), effective d33∗ (electrostrain coefficient), bi-polar strain (Smax), max displacement, dielectric constant (ϵr) and loss (tanδ) are 2500 pC/N, 4604 pm/V, 0.17%, 2.2 μm, 1812 and 2% at 1 kHz, respectively, where the effective d33 or d33∗ is the total output of all layers together. The ultimate target materials for potential substitution with KNN-based ceramics and MLs are commercial PZT-4 and PZT-8.

Analytical solutions of electroelastic fields in piezoelectric thin-film multilayer: applications to piezoelectric sensors and actuators

Analytical expressions are derived for the stresses and electric fields induced in a piezoelectric multilayer deposited on a substrate with lattice misfit and thermal expansion coefficient mismatch. The piezoelectric multilayer can be subjected to an externally applied force, moment and electric potential. The derived formulations can model any number of layers using recursive relations that minimize the computation time. A proper rotation matrix is utilized to generalize the derived expressions to accommodate various orientations allowing each layer to have hexagonal crystal symmetry. The influence of lattice misfit and thermal expansion coefficient mismatch in the presence of externally applied force, moment and electric potential on the state of the electroelastic fields in each layer is evaluated for various applications. Comparison with finite element analysis results shows excellent agreement. The analytical expressions developed here can be useful in designing electromechanical sensors, actuators and optoelectronic devices made from piezoelectric multilayers.

Broadband Ultrasonic Array Transducer From Multilayer Piezoelectric Ceramic With Lowered Co-Firing Temperature.

Increasing array transducer bandwidth (BW) and signal-to-noise ratio (SNR) is a critical issue for producing a high-quality medical ultrasound image. However, array elements with small size tend to have poor sensitivity due to a much higher impedance compared with the electrical impedance of the transmitter and receiver circuit. Implementation of multilayer ceramic (MLC) is an effective way of reducing impedance, and thus, with a potential for improving SNR for an ultrasonic probe. In this work, we fabricated multilayer piezoelectric ceramic with a composition of 0.1Pb(Ni1/3Nb2/3)O3-0.35Pb(Zn1/3Nb2/3)O3-0.15Pb(Mg1/3Nb2/3)O3-0.1PbZrO3-0.3PbTiO3-4mol% excess NiO (PNN-PZN-PMN-PZ-PT), by a roll to roll tape casting process and co-fired with 90Ag/10Pd electrode at a low temperature of 950 °C. Using five-layer MLC (5L-MLC) as obtained, we designed and demonstrated a 5 MHz 32-element array transducer for ultrasonic and photoacoustic imaging. The five-layer transducer element exhibited a BW of 87% at -6 dB, substantially higher than 62% for single-layer ceramic (SLC) element. In addition, the insertion loss was improved by 16.2 dB over the SLC element with an external impedance of 50 Ω . Both the experimental results and theoretical analysis showed that our array transducer made of the PNN-PZN-PMN-PZ-PT MLC is promising for acquiring high-quality ultrasonic and photoacoustic images.

Ferroelectric and piezoelectric properties of PSLZT multilayer / NZFO co-sintered magnetoelectric composites fabricated by tape casting

In this study we investigated the ferroelectric and piezoelectric behaviour of co-sintered magnetoelectric composite fabricated by tape-casting method using Pb(1-x-3y/2)SrxLay(Zrz,Ti(1-z))O3 piezoelectric ceramic with x = 0.06, y = 0.03, z = 0.56 (PSLZT) multilayer and Ni0.6Zn0.4Fe2O4 (NZFO). PSLZT and NZFO powders were prepared by solid state reaction method and respective thick films were fabricated by tape casting method. PSLZT multilayer with Pt inner electrodes were laminated with NZFO and co-sintered at 1060 °C for 2 h to obtain delamination free layered composite. Scanning electron microscopy was employed to analyse the microstructure and interface of the co-sintered multilayer which are crucial for elastic coupling. Micrographs recorded across the cross section of the composites revealed insignificant interdiffusion between the phases. Individual piezoelectric multilayer and magnetoelectric composites were analysed for their ferroelectric behaviour. Piezo Force Microscopy (PFM) and Magnetic Force Microscopy (MFM) were utilized to study the ferroelectric domains and magnetic domains on top surface of PSLZT multilayer and NZFO, respectively in composite structure. Ferroelectric behaviour of PSLZT multilayer - NZFO composite was recorded and compared with 3 layered PSLZT. The values of remanent polarization were found to be 50.6 μC/cm2 and 55 μm/cm2 whereas capacitance at 1 Hz found to be 31.5 nF and 28.9 nF for PSLZT multilayer and PSLZT multilayer – NZFO composite respectively. Piezoelectric coefficient of PSLZT multilayer was found to be 980–1030 pC/N whereas for PSLZT multilayer – NZFO composites it was 1050–1150 pC/N. Magnetoelectric coefficient of 150 mV/cm.Oe was obtained for the same composite structure.

Combining Measurement and Control Functions in the Structure of a Multilayer Piezoelectric Actuator of Nano- and Micro-Motions

The principles of creating precision positioning devices based on the piezoelectric effect were studied. A promising scientific direction in the development of piezo actuators is distinguished – the creation of self-sensing devices simultaneously performing functions of an actuating mechanism (actuator) and primary measuring transducer (feedback sensor). An original structure of an adaptive multilayer piezoelectric actuator of nano- and micro-motions was developed. Its structural scheme is given and its advantages are shown.

Microstructural analysis of co-sintered PSLZT-NZFO layered magnetoelectric composite

ABSTRACTIn this study we made an attempt to fabricate magnetoelectric composite of magnetostrictive NZFO layer on piezoelectric PSLZT multilayer by co-sintering them directly. Microstructural analyses of the layered composite were made to study their interface which is crucial for elastic coupling. Initially (Ni0.7Zn0.3)Fe2O4 and (Sr, La) modified PZT were synthesized by solid oxide route, thick films of them were fabricated by tape casting technique with layer thickness of 100 μm and these layers were laminated together. Here Ag-Pd electrodes were screen printed on individual piezoceramic layers. These NZFO-PSLZT laminated composites were co-sintered between 950 to 1050°C for 2 h. Individual layers of NZFO and six layers of PSLZT with Ag-Pd electrode were also sintered in the same condition for comparison. Scanning electron microscopy was employed to analyze the interface of the co-sintered multilayer. Microstructures of the composite cross section revealed dense thick film with less inter diffusion. Magnetic force microscopy (MFM) was utilized to study the magnetic domains on top surface of individual NZFO layer and NZFO-PSLZT composite. Dielectric behavior of six layered PSLZT was compared with laminated NZFO-PSLZT composite. The properties of co-sintered NZFO-PSLZT composite were correlated with its microstructure.

Modeling of stresses and electric fields in piezoelectric multilayer: Application to multi quantum wells

Exact closed-form expressions have been derived for the stresses and the electric fields induced in piezoelectric multilayers deposited on a substrate with lattice misfit and thermal expansion coefficient mismatch. The derived formulations can model any number of layers using recursive relations that minimize the computation time. A proper rotation matrix has been utilized to generalize the expressions so that they can be used for various growth orientations with each layer having hexagonal crystal symmetry. As an example, the influence of lattice misfit and thermal expansion coefficient mismatch on the state of electroelastic fields in different layers of GaN multi quantum wells has been examined. A comparison with the finite element analysis results showed very close agreement. The analytical expressions developed herein will be useful in designing optoelectronic devices as well as in predicting defect density in multi quantum wells.