Publication

Admittance Matrix of a Trapezoidal Piezoelectric Heterogeneous Bimorph

Publications associées (26)

How to Make Elastomers Piezoelectric?

Piezoelectrics play a significant role in modern electronics and electric devices. Thermal or mechanical stress on such materials induces a change in polarization generating an electric response, which is the sole effect of why they are so interesting. How ...

Wiley2023

Stretchable High Response Piezoelectric Elastomers Based on Polable Polynorbornene Fillers in a Polydimethylsiloxane Matrix

Frank Nüesch, Francis Owusu

To advance the field of piezoelectrics, it is desirable to find materials that combine high piezoelectricity with high elasticity. Applications such as self-sensors, stretchable electronics, soft robots, and energy harvesting would benefit tremendously. Ho ...

WILEY-V C H VERLAG GMBH2022

Optimization of Edge Profile for Improved Anti-Resonance Quality Factor in Lithium Niobate SH0 Resonators

Luis Guillermo Villanueva Torrijo, Silvan Stettler

Thin-film lithium niobate (LNO) has been identified as a promising material platform for enabling high electromechanical coupling and low-loss piezoelectric resonators for filtering applications. In this work, the design and fabrication of fundamental shea ...

IEEE2022

Ferroelectric Effects Probed by in situ Transmission Electron Microscopy

Reinis Ignatans

Ferroelectric perovskite oxides are widely used in sensors, actuators and optical modulators and, at the same time, they show promise for implementation in future applications such as energy storage, memory and cooling devices. At the infancy of the discov ...

EPFL2022

Fabrication, Characterization, and Simulation of Glass Devices with AlN Thin-Film Transducers for Excitation of Ultrasound Resonances

Paul Muralt, Ramin Matloub Aghdam

We present the fabrication of 570-mu m-thick millimeter-sized soda-lime-silicate float-glass blocks with a 1-mu m-thick AlN thin-film piezoelectric transducer sandwiched between thin metallic electrodes and deposited on the top surface. The electromechanic ...

American Physical Society (APS)2021

Dielectric Actuation Techniques at the Nanoscale: Piezoelectricity and Flexoelectricity

Kaitlin Marie Howell

Micro- and nanoelectromechanical systems (MEMS/NEMS) have long shown their potential to disrupt the established technologies. Over the past 15 years, MEMS have become fundamental components in filters, accelerometers, gyroscopes and gas sensors. MEMS are n ...

EPFL2019

Growth, Integration, and Functional Characterization of AlScN Thin Films for RF MEMS Devices

Mohammad Fazel Parsapour Kolour

Mobile communication has grown explosively in recent years, leading to a strong demand for cheap, but high-performing bandpass filters with low insertion loss and smaller size. Surface acoustic wave (SAW) and thin film bulk acoustic wave (BAW) resonators r ...

EPFL2019

Material Parameter Extraction for Complex AlScN Thin Film Using Dual Mode Resonators in Combination with Advanced Microstructural Analysis and Finite Element Modeling

Paul Muralt, Thomas La Grange, Silviu Cosmin Sandu, Mohammad Fazel Parsapour Kolour, Vladimir Pashchenko, Kaoru Yamashita

Accurate property determination of the piezoelectric thin film material Al(1-x)Sc(x)N is necessary for designing the next generation of radio frequency resonators in mobile communication, and for testing results of ab initio calculations. Sound velocity an ...

WILEY2019

Ferroelectric Self-Poling in GeTe Films and Crystals

Jan Hugo Dil

Ferroelectric materials are used in actuators or sensors because of their non-volatile macroscopic electric polarization. GeTe is the simplest known diatomic ferroelectric endowed with exceedingly complex physics related to its crystalline, amorphous, ther ...

2019

Self-sensing, tunable monolayer MoS2 nanoelectromechanical resonators

Andras Kis, Sajedeh Manzeli, Dumitru Dumcenco, Guilherme Migliato Marega

Excellent mechanical properties and the presence of piezoresistivity make single layers of transition metal dichalcogenides (TMDCs) viable candidates for integration in nanoelectromechanical systems (NEMS). We report on the realization of electromechanical ...

Nature Research2019

AlN and AlScN contour mode resonators for MEMS-based RF front ends

Andrea Lozzi

Miniaturization is a simple yet very powerful concept. Applied to devices, it opens to plethora of new applications. Microelectromechanical systems (MEMS) are the result of scaling down the dimensions of devices to the micron range or the nano range (NEMS) ...

EPFL2019

Density control of GaN quantum dots on AlN single crystal

Nicolas Grandjean, Sebastian Pascal Tamariz Kaufmann, Gordon Jens Callsen

Full control over the density and emission properties of GaN quantum dots (QDs) should be feasible, provided that the growth proceeds in the Stranski-Krastanov (SK) growth mode. In this work, we derive the phase diagram for GaN QD formation on AlN by NH3-m ...

2019

Determination of elastic and piezoelectric properties of Al0.84Sc0.16N thin films

Paul Muralt, Mohammad Fazel Parsapour Kolour, Vladimir Pashchenko

In this work, bar- and disk-shaped resonators were fabricated using Al(0.8)4Sc(0.16)N thin film Sensitivity analysis of the resonators' resonance frequencies with respect to the piezoelectric material parameters revealed that resonance analysis can be used ...

IEEE2018

Strain generation and energy-conversion mechanisms in lead-based and lead-free piezoceramics

Dragan Damjanovic

Piezoelectric ceramics generate strain through the intrinsic piezoelectric effect, the motion of ferroelectric domain walls, or through field-induced phase transitions. The enhanced piezoelectric properties observed in morphotropic solid solutions arise fr ...

2018

Internal electric fields and electrode effects in ferroelectric thin films for piezoelectric energy harvesting

Robin Nigon

The continuing decrease of power requirements of electronic circuits offers the potential to deploy wireless systems as embedded sensors for cars or industrial tools, and implanted medical devices. Harvesting ambient vibrations by an appropriate energy har ...

EPFL2017

A concept of wireless and passive very-high temperature sensor

Paul Muralt, Ramin Matloub Aghdam, Andrea Mazzalai

There is a need for sensors capable operating at temperatures above 1000 degrees C. We describe an innovative sensor that might achieve this goal. The sensor comprises two main elements: a thermocouple and a surface acoustic wave (SAW) strain sensor. The c ...

Amer Inst Physics2017

Micromechanical resonators with sub-micron gaps filled with high-k dielectrics

Mariazel de la Candelas Maqueda López

Scaled microelectromechanical (MEMS) resonating devices have generated a great interest for their use in RF front-end architectures for wireless communication, channel-select filters, on-chip signal processing and timing and extreme mas sensing application ...

EPFL2017

Poleable Dielectric Elastomer Composites

Yee Song Ko

As part of the recent efforts on renewable energies, energy harvesting by exploiting environmental motions and vibrations to generate electricity is being enthusiastically developed as a novel kind of green energy source. Piezoelectric materials are a logi ...

EPFL2017

Characterization methodology for lead zirconate titanate thin films with interdigitated electrode structures

Paul Muralt, Robin Nigon, Trygve Magnus Raeder

The accurate evaluation of ferroelectric thin films operated with interdigitated electrodes is quite a complex task. In this article, we show how to correct the electric field and the capacitance in order to obtain identical polarization and CV loops for a ...

Amer Inst Physics2017

Enhanced piezoelectric properties of c-axis textured aluminium scandium nitride thin films with high scandium content: influence of intrinsic stress and sputtering parameters

Paul Muralt, Silviu Cosmin Sandu, Clemens Benedict Nyffeler, Gabriel Christmann, Stefan Mertin, Mohammad Fazel Parsapour Kolour, Vladimir Pashchenko

Aluminium scandium nitride (ASN) exhibits a largely enhanced piezoelectric response as compared to aluminium nitride (AlN), which makes it an upcoming piezoelectric material for use in next generation RF filters, sensors, actuators and energy harvesting de ...

Ieee2017