Recent Progress in Flexible Multiferroics

A great deal of interest has grown in both academia and industry toward flexible multiferroics in the recent years. The coupling of ferromagnetic properties with ferroelectric properties in multiferroic materials opens up many opportunities in applications such as magnetoelectric random access memories, magnetic field sensors, and energy harvesters. Multiferroic materials on a flexible platform bring an exciting opportunity for the next generation of consumer electronics owing to their unique characteristics of wearability, portability, and weight reduction. However, the fabrication of flexible multiferroic devices is still a great challenge due to various technical difficulties, including the requirement of high growth temperature of the oxide-based multiferroic materials, their lattice mismatch with the flexible substrates, and the brittleness of the functional layers. In this review article, we will discuss different methods of fabricating flexible or even freestanding oxide films to achieve flexible electronics. This article will address the benefits and challenges of each synthesis method in terms of interlayer interactions and growth parameters. Furthermore, the article will include an account of the possible bending limits of different flexible substrates without degrading the properties of the functional layer. Finally, we will address the challenges, opportunities, and future research directions in flexible multiferroics.

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ZnSxO1-x Films Grown on Flexible Substrates

MRS Proceedings ◽

10.1557/opl.2012.417 ◽

2012 ◽

Vol 1394 ◽

Cited By ~ 1

Author(s):

Jesse Huso ◽

Hui Che ◽

John L. Morrison ◽

Dinesh Thapa ◽

Michelle Huso ◽

...

Keyword(s):

Flexible Electronics ◽

Flexible Substrates ◽

Semiconductor Films ◽

Ethylene Propylene ◽

Transmission Spectroscopy ◽

Fluorinated Ethylene Propylene ◽

Potential Substrate

ABSTRACTBandgap engineered ZnSxO1-x films were grown on Fluorinated Ethylene Propylene (FEP) substrates and analyzed using transmission spectroscopy. FEP is considered as a potential substrate for application in flexible electronics and semiconductor films.

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Facile Synthesis of Silver Nanoparticles and Preparation of Conductive Ink

Nanomaterials ◽

10.3390/nano12010171 ◽

2022 ◽

Vol 12 (1) ◽

pp. 171

Author(s):

Gui Bing Hong ◽

Yi Hua Luo ◽

Kai Jen Chuang ◽

Hsiu Yueh Cheng ◽

Kai Chau Chang ◽

...

Keyword(s):

Silver Nanoparticles ◽

Electrical Resistivity ◽

Reaction Time ◽

Reaction Temperature ◽

Ph Value ◽

Chemical Reduction ◽

Flexible Substrate ◽

Synthesis Method ◽

Future Research ◽

Conductive Ink

In the scientific industry, sustainable nanotechnology has attracted great attention and has been successful in facilitating solutions to challenges presented in various fields. For the present work, silver nanoparticles (AgNPs) were prepared using a chemical reduction synthesis method. Then, a low-temperature sintering process was deployed to obtain an Ag-conductive ink preparation which could be applied to a flexible substrate. The size and shape of the AgNPs were characterized by ultraviolet–visible spectrophotometry (UV-Vis) and transmission electron microscopy (TEM). The experiments indicated that the size and agglomeration of the AgNPs could be well controlled by varying the reaction time, reaction temperature, and pH value. The rate of nanoparticle generation was the highest when the reaction temperature was 100 °C within the 40 min reaction time, achieving the most satisfactorily dispersed nanoparticles and nanoballs with an average size of 60.25 nm at a pH value of 8. Moreover, the electrical resistivity of the obtained Ag-conductive ink is controllable, under the optimal sintering temperature and time (85 °C for 5 min), leading to an optimal electrical resistivity of 9.9 × 10−6 Ω cm. The results obtained in this study, considering AgNPs and Ag-conductive ink, may also be extended to other metals in future research.

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Experimental Study of the High Cycle Fatigue of Thin Film Metal on Polyethylene Terephthalate for Flexible Electronics Applications

ASME 2009 InterPACK Conference, Volume 1 ◽

10.1115/interpack2009-89247 ◽

2009 ◽

Cited By ~ 5

Author(s):

Khalid Alzoubi ◽

Susan Lu ◽

Bahgat Sammakia ◽

Mark Poliks

Keyword(s):

Thin Film ◽

Thin Films ◽

Polyethylene Terephthalate ◽

Flexible Electronics ◽

Electrical Resistance ◽

Thermal Stresses ◽

Electronic Systems ◽

Total Width ◽

Flexible Substrates ◽

Polyethylene Naphthalate

Flexible electronics represent an emerging area in the electronics packaging and systems integration industry with the potential for new product development and commercialization in the near future. Manufacturing electronics on flexible substrates will produce low cost devices that are rugged, light, and flexible. However, electronic systems are vulnerable to failures caused by mechanical and thermal stresses. For electronic systems on flexible substrates repeated stresses below the ultimate tensile strength or even below the yield strength will cause failures in the thin films. It is known that mechanical properties of thin films are different from those of bulk materials; so, it is difficult to extrapolate bulk material properties on thin film materials. The objective of this work is to study the behavior of thin-film metal coated flexible substrates under high cyclic bending fatigue loading. Polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) are widely used substrates in the fabrication of microelectronic devices. Factors affecting the fatigue life of thin-film coated flexible substrates were studied, including thin film thickness, temperature, and humidity. A series of experiments for sputter-deposited copper on PET substrates were performed. Electrical resistance and crack growth rate were monitored during the experiments at specified time intervals. High magnification images were obtained to observe the crack initiation and propagation in the metal film. Statistical analysis based on design of experiments concepts was performed to identify the main factors and factor’s interaction that affect the life of a thin-film coated substrate. The results of the experiments showed that the crack starts in the middle of the sample and slowly grows toward the edges. Electrical resistance increases slightly during the test until the crack length covers about 90% of the total width of the sample where a dramatic increase in the resistance takes place.

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Warehouse configuration in omni-channel retailing: a multiple case study

International Journal of Physical Distribution & Logistics Management ◽

10.1108/ijpdlm-01-2019-0034 ◽

2019 ◽

Vol 50 (5) ◽

pp. 509-533

Author(s):

Joakim Hans Kembro ◽

Andreas Norrman

Keyword(s):

Case Studies ◽

Conceptual Models ◽

Construction Material ◽

Multiple Case Study ◽

Consumer Electronics ◽

Future Research ◽

Content Type ◽

Automation Systems ◽

Multiple Case

Purpose The purpose of this study is to explore warehouse configuration in omni-channel retailing. Design/methodology/approach A multiple case study is conducted with six large omni-channel retailers from three different sectors. Findings The study shows an increase in the number, variation and frequency of flows passing through omni-channel warehouses. Along with an increased variety of stock keeping units (including singles vs multipacks), there is an increase in the complexity of planning and coordination of order fulfillment. Retailers test a mix of different solutions for storage and picking and partly shift focus to advanced sorting operations. The companies already have or plan to invest in substantial automation systems, which emphasize the importance of capturing and using accurate master data. Research limitations/implications The study highlights the need to understand the interrelations and co-development of configuration elements in omni-channel warehousing. The findings also suggest that a successful transformation requires increased collaboration with upstream and downstream partners. Conceptual models are developed to illustrate strategies and development paths in omni-channel warehousing, and suggestions for future research are summarized in a research agenda. A research limitation is the focus on Swedish retailers in three sectors (fashion, consumer electronics and DIY/construction material). Future studies can include additional sectors, extend the geographical scope and explore cross-regional differences. Practical implications As one of the few deeper case studies on omni-channel warehousing, practitioners will find new configurations described and analyzed here. Along with conceptual models, a synthesis of challenges and potential solutions are presented to support retailers’ practical analysis and decision making. Originality/value This is one of the first multiple case studies that go deeper into omni-channel warehouse configuration, which is of increasing importance to both scholars and practitioners in the field.

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One-pot synthesis of a stable and cost-effective silver particle-free ink for inkjet-printed flexible electronics

Journal of Materials Chemistry C ◽

10.1039/d0tc03864d ◽

2020 ◽

Vol 8 (46) ◽

pp. 16443-16451

Author(s):

Wendong Yang ◽

Florian Mathies ◽

Eva L. Unger ◽

Felix Hermerschmidt ◽

Emil J. W. List-Kratochvil

Keyword(s):

Flexible Electronics ◽

Silver Particle ◽

Low Cost ◽

Cost Effective ◽

Good Stability ◽

Flexible Substrates ◽

One Pot ◽

One Pot Synthesis ◽

Do It Yourself

A do-it-yourself silver particle-free ink is presented, which shows good stability, low cost and excellent printability. The ink is formulated in selected alcohols. Highly conductive silver patterns were printed on both glass and flexible substrates.

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Some practical constraints and solutions for optical camera communication

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2019.0191 ◽

2020 ◽

Vol 378 (2169) ◽

pp. 20190191 ◽

Cited By ~ 7

Author(s):

Weijie LIU ◽

Zhengyuan Xu

Keyword(s):

Wireless Communication ◽

Communication Systems ◽

Consumer Electronics ◽

Frame Rate ◽

Future Research ◽

Optical Wireless Communication ◽

Optical Wireless ◽

Atmospheric Scattering ◽

Practical Constraints ◽

Optical Camera Communication

Mobile wireless communication heavily relies on the radio frequency to convey message and data. However, its limited spectrum can hardly meet the demands for the future high data rate applications. Optical wireless communication, in particular visible light communication, opens up vast optical spectrum for communication, and meanwhile can retrofit the light sources as the communication transmitters in the existing working or living environments. In conjunction with the ubiquitous cameras in hand-held consumer electronics such as smartphones and pads, optical camera communication (OCC) further takes advantages of image sensors as the communication receivers and realizes low-cost communication systems. This article first provides an overview of OCC systems. It then addresses some practical constraints, ranging from sensor low frame rate and instability, rolling shutter readout, to visual qualities of displayed images and videos, and link blockage between the transmitter and receiver. Accordingly, it introduces existing and new solutions to deal with those constraints by data modulation, newly developed camera structures, post-processing of sensed signals and non-line of sight OCC as a new form. In particular, indirect paths by either the indoor surface reflection or the outdoor atmospheric scattering are explored for link connectivity under blockage. Finally, some future research directions are suggested. This article is part of the theme issue ‘Optical wireless communication’.

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Direct Printing of Capacitive Touch Sensors on Flexible Substrates by Additive E-Jet Printing With Silver Nanoinks

Volume 1: Processing ◽

10.1115/msec2016-8740 ◽

2016 ◽

Author(s):

Hantang Qin ◽

Yi Cai ◽

Jingyan Dong ◽

Yuan-Shin Lee

Keyword(s):

Flexible Electronics ◽

Simple Structure ◽

Rapid Prototype ◽

Flexible Substrates ◽

Optimized Design ◽

Flexible Sensors ◽

Direct Printing ◽

Electrode Length ◽

Jet Printing ◽

Good Transparency

In this paper, techniques of direct printing of capacitive touch sensors on flexible substrates are presented. Capacitive touch sensors were fabricated by using electrohydrodynamic inkjet (E-jet) printing onto flexible substrates. Touch pad sensors can be achieved with optimized design of silver nanoink tracks. An analytical model was developed to predict touch pad capacitance, and experiments were conducted to study the effects of sensor design (e.g. number of electrodes, electrode length, and electrode distance) on the capacitance of printed coplanar capacitance touch sensors. Details of the fabrication techniques were developed to enable rapid prototype flexible sensors with simple structure and good sensitivity. The presented techniques can be used for the on-demand fabrication of different conductive patterns for flexible electronics with high-resolution and good transparency.

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Development of Process-Recipes for Multi-Layer Circuitry Printing With Z-Axis Interconnects Using Aerosol-Jet Nanoparticle Ink

ASME 2020 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems ◽

10.1115/ipack2020-2664 ◽

2020 ◽

Author(s):

Pradeep Lall ◽

Jinesh Narangaparambil ◽

Ved Soni ◽

Scott Miller

Keyword(s):

Flexible Electronics ◽

Flow Line ◽

Unit Length ◽

Scale Up ◽

Single Layer ◽

Consumer Electronics ◽

Shear Load ◽

Load To Failure ◽

Jet Printing ◽

Aerosol Jet Printing

Abstract Flexible electronics is a rapid emerging trend in consumer-electronics with ever-increasing applications showing feasibility of functionality with flexibility. Aerosol Jet printing technology has gained rapid acceptance for additive printing owing to non-contact deposition and ability to print on non-planar surfaces. Prior work on aerosol-jet print processes primarily focuses on single-layer printing, taking into account different parameters such as mass flow, line width, sintering conditions, and overspray. Flexible PCBs in complex applications are envisioned to be multi-layered, involving stacking of interconnections and connection between successive layers through use of z-axis connections. Aerosol-jet printing method allows the printing of interconnections with a number of inks including silver, copper, and carbon with fine lines and spaces in neighborhood of 10μm. Process recipes for manufacturing multilayer circuits and system scale-up methods are required. The objective of the paper is to establish process-recipes for z-axis interconnects and quantify process variability with Aerosol-jet print process needed for high volume scale-up. Conductive interconnects have been printed using the ultrasonic atomizer and the interlayer dielectrics have been printed using the pneumatic atomizer. The effect of thermal sintering on the performance of the printed circuits has been quantified through measurements of interconnect resistance and shear load to failure. This paper explores the printing of multi-layer upto 8 conductive layers. Sintering profile for lower resistance per unit length and higher shear load to failure was tested.

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First evaluation of growth parameters in clonal test with wild cherry

Journal of Forest Science ◽

10.17221/2140-jfs ◽

2008 ◽

Vol 53 (No. 2) ◽

pp. 57-65 ◽

Cited By ~ 2

Author(s):

M. Hajnala ◽

M. Lstibůrek ◽

J. Kobliha

Keyword(s):

Czech Republic ◽

Prunus Avium ◽

Growth Parameters ◽

Mixed Linear Model ◽

Future Research ◽

Wild Cherry ◽

The Czech Republic ◽

Research Activities ◽

Clonal Test ◽

Clonal Trial

A 6-year-old clonal trial with 13 clones of wild cherry (<i>Prunus avium</i> L.) was evaluated during the summer of 2004 at 6 different sites in the Czech Republic. Observed traits were the stem height, stem diameter, health status, and mortality. The mixed linear model was implemented with either independent or the autoregressive error structure. The later provided better fit to the data. At this age, only one clone outperformed the remaining ones in volume production. Suggestions for future research activities are provided that should lead to the establishment of long-term breeding programs with wild cherry in the Czech Republic.

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