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NXP Semiconductors N.V. (NASDAQ:NXPI) today announced the world’s smallest single-chip SoC solution – the MC9S08SUx microcontroller (MCU) family – with an integrated 18V-to-5V LDO and MOSFET pre-driver that delivers ultra-high-voltage solution for drones, robots, power tools, DC fan, healthcare and other low-end brushless DC electric motor control (BLDC) applications. Extending the company’s S08 family of MCUs, the robust 8-bit MC9S08SUx microcontroller family offers 4.5V~18V supply voltage range with lower bill of materials (BOM) cost and tighter integration for higher performance and reliability. The new SoC units address the growing demand to replace multiple device solutions with a single MCU to reduce cost and system size, while simplifying integration and layout for space-constrained use cases.

“The market trend is pointing towards integrated solutions that save system size and cost, and NXP is leading the industry as the only provider to offer a single-chip offering with integrated microcontroller and MOSFET pre-driver in a 4x4x0.65mm form factor, which also makes it possible to cut the printed circuit board size in half,” said Geoff Lees, senior vice president and general manager of the microcontroller business line at NXP. “Historically, several devices were needed to address the needs of BLDC motor control applications, which can be expensive and large in size; our latest addition to the S08 MCU family underscores our dedication to solving unique challenges by introducing new microcontrollers for the broad market.”

Based on the HCS08 core, the MC9S08SUx leverages the enhanced S08L central processor unit with three-phase MOSFET pre-drivers to deliver all-in-one unit for 4.5V-18V motor control applications. The single-chip MC9S08SUx MCU removes the need for Low Drop Out (LDO) voltage regulator(s), operational amplifiers, and pre-drivers for a streamlined, cost-effective solution. Additionally, NXP has integrated virtually all of the necessary features in BLDC motor control, including zero crossing point detection, pulse width measurement, over voltage protection and over current protection, enabling developers to simply configure registers and easily use the functions in applications. The MC9S08SUx family also includes amplifiers for current measurement and supports three high-side PMOSes as well as three low-side NMOSes.

NXP’s S08 microcontrollers, including the new MC9S08SUx family, are supported by CodeWarrior IDE. FreeMASTER support is offered as run-time debugging tool. In addition, IAR Embedded Workbench supports the NXP S08 MCU portfolio, offering a single toolbox complete with configuration files, code examples and project templates. IAR Embedded Workbench support for the MC9S08SUx MCU family will be available March 2017.

“The leading optimization technology in IAR Embedded Workbench helps developers to maximize performance and minimize power consumption for applications based on the new MC9S08SUx MCU family from NXP,” said Jan Nyrén, Product Manager, IAR Systems.

Imec and Holst Centre (initiated by imec and TNO) have developed a novel phase-tracking receiver bringing further power and cost reduction for the next generations of Bluetooth and IEEE802.15.4 radio chips. The ultra-low power digital-style receiver is 3x smaller than the current state-of-the-art. It supports supply voltages as low as 0.85V and consumes less than 1.6mW peak. An innovative low power antenna impedance detection technique enhances radio performance, especially for wearables or implantable applications.

The ongoing evolution towards an intuitive IoT has created unprecedented opportunities in various application domains. However, the deployment of massive numbers of interconnected sensors requires ultra-low power solutions enabling multi-year battery life. To increase the autonomy of sensors, imec develops ultra-low power wireless technology for IoT applications, such as next-generation Bluetooth Low Energy and IEEE 802.15.4.

Imec’s novel receiver concept features sub-1nJ/bit energy efficiency and low supply voltage operation at 0.85V while maintaining similar RX sensitivity as best-in-class products. The receiver employs digital phase-tracking to directly translate the RF input to demodulated digital data. A digitally-controlled oscillator (DCO) is used instead of a power hungry phase locked loop (PLL). The receiver, implemented in 40nm CMOS, is only 0.3mm2, which is at least 3x smaller compared to the state-of-the-art. Due to this small size it can be manufactured at strongly reduced cost.

Especially in wearable or implantable devices, the antenna impedance can dynamically change due to variations in a device’s position or surroundings. This can deteriorate the radio’s performance and degrade battery lifetime. Imec demonstrated a fully integrated, sub-mW impedance detection technique for ultra-low power radios, enabling tunable matching between the antenna and the radio front-end. This technique can be implemented in an adaptive radio front-end to further improve receiver sensitivity and transmitter efficiency in the presence of antenna impedance variations.

“This innovative receiver concept will not only serve the new Bluetooth 5 devices, but provides our industrial partners a long term competitive advantage for multiple new generations of Bluetooth and 802.15.4 radios, still to come,” says Kathleen Philips, Program Director Perceptive Systems at imec/Holst Centre. “This great achievement is a confirmation of our continuous efforts to push the technology limits toward ever higher performance, lower power consumption and smaller form factor, which are essential features for internet-of-things radio solutions.”

imec and holst

Eutelsat Communications (NYSE Euronext Paris: ETL),a satellite operator, and STMicroelectronics (NYSE: STM) have achieved a new milestone with a new-generation chip that will power Eutelsat’s SmartLNB interactive terminal.

ST’s advanced, low-power System-on-Chip (STiD337) represents a big step down in the overall cost of interactive satellite terminals. The STiD337’s first adoption is in Eutelsat’s SmartLNB, lowering cost, upgrading service, and significantly reducing power consumption.

The SmartLNB is an electronic feed that replaces the traditional Ku-band reception of DTH satellite signals, embedding one or more satellite tuners/demodulators directly inside the LNB (low-noise block) and adding a narrowband return link optimized for transmissions of IP packets. The SmartLNB enables a wide range of connected TV applications, providing a transparent bidirectional IP link compatible with existing services. Not limited to the TV and broadcast market, applications also cover the exploding sector of connected objects (Machine-to-Machine, Internet of Things, SCADA, home-automation, Smart Buildings, etc.) with a cost-effective solution via satellite.

ST has employed its very low-power 28nm FD-SOI (Fully Depleted Silicon on Insulator) process technology that enables deep sleep and auto wake up for the system. With a maximum 3.5W power dissipation at full speed and less than 50mW (typical) during sleep, the STiD337 is the most power-efficient device available today to take the SmartLNB to a new level of performance and efficiency.

The STiD337 adds the latest DVB-S2X satellite standard for the forward link, as well as GSE (Generic Stream Encapsulation) for efficient data handling; it can achieve throughput of over 100Mb/sec. The return path implements a software-radio approach that is optimized for the enhanced spread-spectrum technique with asynchronous access typically used for the SmartLNB. The device also includes the full complement of hardware mechanisms to support real-time multiple-access techniques. The return modulation is calculated on the internal processors. The platform includes a dual ARM Cortex-A9 core with NEON co-processors and four ST231 DSP offload coprocessors to enhance its compute power and ensure complete flexibility in the choice of return-channel modulation type.

The new SoC will be available in secure and standard versions. The secure version includes pre-loaded encryption keys, serial numbers, safe-boot, and many other features to increase the level of protection of data-delivering and gathering operations by the SmartLNB.

“We wanted a step change in the cost and performance for the next generation of our SmartLNB interactive service. We know from our customers that security is a major concern and we wanted to address that head on. Furthermore, with satellite terminals becoming more ubiquitous and employed in a greater range of use cases we needed to pay even greater attention to power consumption,” said Antonio Arcidiacono, Director of Innovation at Eutelsat. “The design objectives we set have all been met and we’re aiming to roll out higher-performance, lower-cost, secure, and above all, lower-power consumption SmartLNB terminals based on ST’s new satellite SoC by the end of 2017.”

“Working closely with Eutelsat, we’ve developed the lowest-cost, lowest-power, secure, and most advanced interactive satellite-modem SoC to date,” said Jocelyne Garnier, Group VP, General Manager, Aerospace, Defense, and Legacy Division, STMicroelectronics. “From the outset we knew we could bring innovations to the market that played to many of the strengths we have in ST, especially in digital satellite systems, our system-on-chip experience, our low-power technologies, and of course, our security IP.”

ST provides a hardware evaluation platform, a Linux-based operating system, and a basic driver set. Final production samples of the STiD337 are available now and full production is scheduled for May 2017. Further information is available on ST.com and under NDA.

Surface roughness reduction is a really big deal when it comes to fundamental surface physics and while fabricating electronic and optical devices. As transistor dimensions within integrated circuits continue to shrink, smooth metallic lines are required to interconnect these devices. If the surfaces of these tiny metal lines aren’t smooth enough, it substantially reduces their ability to conduct electrical and thermal energy — decreasing functionality.

A group of engineers at the University of Massachusetts Amherst are now reporting an advance this week in Applied Physics Letters, from AIP Publishing, in the form of modeling results that establish electrical surface treatment of conducting thin films as a physical processing method for reducing surface roughness.

Sequence of snapshots from a computer simulation of electric-field-driven morphological evolution of a copper thin film, demonstrating current-induced smooth surface. Credit: Du and Maroudas

Sequence of snapshots from a computer simulation of electric-field-driven morphological evolution of a copper thin film, demonstrating current-induced smooth surface. Credit: Du and Maroudas

“We’ve been thinking hard about this roughness problem for many years, since showing that electric currents can be used to inhibit surface cracking,” said Dimitrios Maroudas, co-author and a professor in the Department of Chemical Engineering. “So as soon as we developed the computational tools to attack the full film roughness problem, we got to work.”

The group’s work focused on using a copper film on a silicon nitride layer to quantify the model parameters for their simulations and make comparisons with available experimental findings, which they were able to reproduce.

“Surface electromigration is the key physical concept involved,” Maroudas explained. “It’s the directed transport of atoms on the metal surface due to the so-called electron wind force, which expresses the transfer of momentum from the electrons of the metal moving under the action of an electric field to the atoms (ions) — biasing atomic migration.”

Think of it as akin to the diffusion of ink in flowing water. “Electromigration’s role in the transport of surface atoms is analogous to that of convection due to flow on the transport of ink within the water,” Maroudas said. “The combined effects of a well-controlled applied electric field and rough surface geometry drive the atoms on the metal surface to move from the hills of the rough surface morphology to the neighboring valleys, which eventually smooth away the rough surfaces.”

This work is significant, particularly within the microelectronics realm, because it establishes the electrical treatment of metallic (conducting) films as a viable physical processing strategy for reducing their surface roughness.

“Our approach is qualitatively different than traditional mechanical polishing or ion-beam irradiation techniques,” said Lin Du, co-author and a doctoral student working with Maroudas. “It directly influences the driven diffusion of surface atoms precisely, which affects surface atomic motion and enables a smooth surface all the way down to the atomic level.”

The required electric field action can be conveniently controlled macroscopically: simply choose a direction, adjust the voltage, and flip a switch “on.”

“While studying the phenomenon, we discovered that a sufficiently strong electric field can bring the metallic surface to an atomically smooth state,” Du said. “The required electric field strength depends largely on the field direction and surface material properties of the metallic film — such as film texture and surface diffusional anisotropy, because in surfaces of crystalline materials diffusion is faster along certain preferred directions.”

A true irony here is that “electromigration is best known for its damaging effects within metallic interconnects — underlying crucial materials reliability problems in many generations of microelectronics,” Maroudas said.

As far as applications, since this work establishes the principles to create smoother conducting material surfaces, “it can be used for fabricating and processing nanoscale-thick metallic components within electronic and optical devices, which require atomic-scale smoothness,” Maroudas said. “The ability to reduce the surface roughness of metallic components, such as interconnects within integrated circuits, will significantly improve their performance as well as durability and reliability.”

What’s the next step for the engineers? “We’re currently exploring how the effectiveness of the method depends on the metallic film texture (or surface crystallographic orientation), the film’s wetting of the substrate, and the electric field direction with respect to certain surface crystallographic directions,” Maroudas said.

The group’s immediate goal is “to optimize the electrical treatment technique, and to identify the conditions for minimizing the required electric field strength, as well as the cost of applying this technique,” he added. “Our next natural step should be a partnership with an experimental laboratory with the proper expertise to carry out tests that will help us move from proof of concept to an enabling technology.”

Imec, the research and innovation hub in nano-electronics and digital technologies, today announced that their 200mm gallium nitride-on-silicon (GaN-on-Si) e-mode power devices with a pGaN gate architecture showed no degradation after heavy ion and neutron irradiation. The irradiation tests were performed in collaboration with Thales Alenia Space, a leader in innovative space systems. The results demonstrate that imec’s 200mm GaN-on-Si platform delivers state-of-the-art GaN-based power devices for earth as well as for space applications.

GaN-on-silicon transistors operate at higher voltages, frequencies and temperatures than their silicon counterparts. This makes them the ideal candidates for power conversion devices as they show less power losses in electricity conversion. First-generation GaN-based power devices are used today and will play a key role in the power conversion of future electronic devices such as battery chargers, smartphones, computers, servers, automotive, lighting systems and photovoltaics.

Imec has been  developing the next-generation of GaN-based power devices with improved performance and reliability. Imec’s latest 200mm GaN-on-Si platform shows good  wafer-to-wafer reproducibility and low dynamic Rdson. The platform is currently available for dedicated development or technology transfer to imec’s current and future partners.

imec Ron

Imec’s latest generation of  200mm GaN-on-Si e-mode pGaN devices were irradiated with heavy ions (Xenon) and neutrons. Pre and post irradiation tests revealed that there was no permanent degradation of transistor characteristics: no shifts in threshold voltage nor gate rupture. The excellent radiation hardness of imec’s devices is important, as it enables applications in space, where fluxes of heavy ions and neutrons can damage electronic circuits in satellites and space stations.

Thales Alenia Space Belgium has surveyed, since many years, the evolution in the field of wide band gap devices. These family of components is promising for a significant increase in performances. But, robustness to space radiation is mandatory for electronic devices in our equipment’s. The result obtained with Imec’s GaN-on-Si devices is an important step in the way to space based power conversion applications.

“These results are important to start using this promising technology for space applications. Also, it demonstrates that our 200mm GaN-on-Si platform has reached a high level of technology readiness and can be adopted by industry,” stated Rudi Cartuyvels, Executive Vice President at imec. “At imec, we use 200mm silicon substrates for GaN epitaxy and this technology can be used on 200mm CMOS-compatible infrastructure. Thanks to innovations in transistor architecture and substrate technology, we’ve succeeded in making GaN devices on larger wafer diameters than used today, which brings lower cost perspectives for the second generation of GaN-on-Si power devices. Imec is also looking beyond today’s technology, exploring novel substrates, higher level of integrations and novel devices.”

These results were achieved in the framework of the European Space Agency (ESA) project “ESA AO/1-7688/13/NL/RA”, GaN devices for space based DC-DC power conversion applications.

Andrew Barnes ESA Technical Officer overseeing the project stated: “GaN is a critical technology for future space missions with a wide range of potential applications, including smaller size, higher efficiency DC-DC power conversion subsystems. These results, obtained from the first phase of an ESA GSTP project, are important and show that the p-GaN devices developed by imec offer excellent radiation robustness for operation in space. In the second phase of the project it is planned to industrialize this technology in readiness for a future space qualification program”. The European Space Agency (ESA) is Europe’s gateway to space. Its mission is to shape the development of Europe’s space capability and ensure that investment in space continues to deliver benefits to the citizens of Europe and the world.

A new optical nanosensor enabling more accurate measurement and spatiotemporal mapping of the brain also shows the way forward for design of future multimodal sensors and a broader range of applications, say researchers in an article published in the current issue of Neurophotonics. The journal is published by SPIE, the international society for optics and photonics.

Neuronal activity results in the release of ionized potassium into extracellular space. Under active physiological and pathological conditions, elevated levels of potassium need to be quickly regulated to enable subsequent activity. This involves diffusion of potassium across extracellular space as well as re-uptake by neurons and astrocytes.

Measuring levels of potassium released during neural activity has involved potassium-sensitive microelectrodes, and to date has provided only single-point measurement and undefined spatial resolution in the extracellular space.

With a fluorescence-imaging-based ionized-potassium-sensitive nanosensor design, a research team from the University of Lausanne was able to overcome challenges such as sensitivity to small movements or drift and diffusion of dyes within the studied region, improving accuracy and enabling access to previously inaccessible areas of the brain.

The work by Joel Wellbourne-Wood, Theresa Rimmele, and Jean-Yves Chatton is reported in “Imaging extracellular potassium dynamics in brain tissue using a potassium-sensitive nanosensor.” The article is freely available for download.

“This is a technological breakthrough that promises to shed new light — both literally and figuratively — on understanding brain homeostasis,” said Neurophotonics associate editor George Augustine, of Duke University. “It not only is much less invasive than previous methods, but it adds a crucial spatial dimension to studies of the role of potassium ions in brain function.”

This potassium-sensitive nanosensor is likely to aid future investigations of chemical mechanisms and their interactions within the brain, the authors note. The spatiotemporal imaging created by collected data will also allow for investigation into the possible existence of potassium micro-domains around activated neurons and the spatial extent of these domains. The study confirms the practicality of the nanosensor for imaging in the extracellular space, and also highlights the range of possible extensions and applications of the nanosensor strategy.

Rice University researchers have modeled a nanoscale sandwich, the first in what they hope will become a molecular deli for materials scientists.

Their recipe puts two slices of atom-thick graphene around nanoclusters of magnesium oxide that give the super-strong, conductive material expanded optoelectronic properties.

Rice materials scientist Rouzbeh Shahsavari and his colleagues built computer simulations of the compound and found it would offer features suitable for sensitive molecular sensing, catalysis and bio-imaging. Their work could help researchers design a range of customizable hybrids of two- and three-dimensional structures with encapsulated molecules, Shahsavari said.

The research appears this month in the Royal Society of Chemistry journal Nanoscale.

The scientists were inspired by experiments elsewhere in which various molecules were encapsulated using van der Waals forces to draw components together. The Rice-led study was the first to take a theoretical approach to defining the electronic and optical properties of one of those “made” samples, two-dimensional magnesium oxide in bilayer graphene, Shahsavari said.

“We knew if there was an experiment already performed, we would have a great reference point that would make it easier to verify our computations, thus allowing more reliable expansion of our computational results to identify performance trends beyond the reach of experiments,” Shahsavari said.

Graphene on its own has no band gap – the characteristic that makes a material a semiconductor. But the hybrid does, and this band gap could be tunable, depending on the components, Shahsavari said. The enhanced optical properties are also tunable and useful, he said.

“We saw that while this single flake of magnesium oxide absorbed one kind of light emission, when it was trapped between two layers of graphene, it absorbed a wide spectrum. That could be an important mechanism for sensors,” he said.

Shahsavari said his group’s theory should be applicable to other two-dimensional materials, like hexagonal boron-nitride, and molecular fillings. “There is no single material that can solve all the technical problems of the world,” he said. “It always comes down to making hybrid materials to synergize the best features of multiple components to do a specific job. My group is working on these hybrid materials by tweaking their components and structures to meet new challenges.”

STMicroelectronics (NYSE: STM), a global semiconductor developer serving customers across the spectrum of electronics applications and a top MEMS supplier, DSP Group Inc. (NASDAQ: DSPG), a global provider of wireless chipset solutions for converged communications, and Sensory Inc., the developer of voice interface and keyword-detect algorithms, have revealed details for a highly power-efficient, voice-detecting and -processing microphone that delivers keyword-recognition capabilities in a compact package.

The small System-in-Package (SiP) device integrates a low-power ST MEMS microphone enabled by DSP Group’s ultra-low power voice-processing chip and Sensory’s voice-recognition firmware. The solution leverages ST’s advanced packaging technology to achieve a powerful yet lightweight package, extremely long battery runtimes, and advanced functionality.

Although typical wake-on-sound microphones eliminate the need for users to touch the device to wake it from sleep mode, they suffer from limited processing power and wake the main system processor to recognize the received instruction. Using the powerful computation capabilities from DSP Group, ST’s microphone detects and recognizes instructions without waking the main system, enabling energy-efficient, intuitive, and seamless interactions for users speaking to voice-operated appliances like smart speakers, TV remotes, and smart home systems.

The new microphone solution taps DSP Group’s HDClear ultra-low power audio processing chip to significantly reduce energy consumption, extending the lifetime of battery-operated equipment for several years without the need to recharge or replace battery. Responses to voice commands are also faster, because the system acts on the instruction immediately without first having to recognize it.

“Unlike previous existing solutions, this microphone doesn’t just listen to voices – it immediately understands the commands, too, without using the power and computation resources of the main processor,” commented Andrea Onetti, MEMS and Sensors Division General Manager, STMicroelectronics. “This smart integration step is a key enabler for the voice interfaces that are being added to IoT objects and applications, including those contributing to Industry 4.0.”

“As voice becomes the default user interface, more and more innovative products embrace smart voice-processing technology. Our solution combines a small footprint, high integration, and the low-power consumption needed to enable seamless and effective voice user interfaces in battery-operated devices,” said Ofer Elyakim, CEO of DSP Group. “Collaboration with industry leaders ST and Sensory on this smart microphone brings to market a powerful yet energy-efficient solution with best-in-class performance, which makes it a perfect match for any smart system that needs to incorporate high-quality voice capabilities.”

Todd Mozer, CEO of Sensory, added, “Voice activation has the potential to transform the way people interact with all kinds of electronic equipment in the home, while on the go, or at work. ST’s new highly integrated solution, leveraging our latest-generation firmware, is an important enabler for OEMs seeking to deliver a natural and fluid user experience.”

First prototypes of ST’s new command-recognition microphone will be available by the end of Q1 2017 with volume production in early 2018.

Gas sensors used for leakage alerts and air quality monitoring are essential in our daily lives. Towards a ubiquitous society, smart gas sensors, which perform signal processing and communication besides sensing, have attracted much attention. In addition, integrating these functions into a single chip leads to low-cost and miniature smart gas-sensing systems.

Semiconductor gas sensors, which are the most widely used gas sensors, require a sensor material to be heated to several hundreds of degree Celsius. Therefore, in order to integrate these gas sensors with electronic circuits, a micro-hotplate (MHP), which is a MEMS-based heating structure, is required to thermally isolate the sensor and the circuits. The MHP is generally mechanically unstable, and there exists a tradeoff between the mechanical stability and thermal isolation property.

Recently, a research team at the Department of Electrical and Electronic Information Engineering at Toyohashi University of Technology proposed the employment of SU-8 as a supporting material for the MHP, in order to improve the mechanical stability, while ensuring the thermal isolation property. Furthermore, SU-8 is a polymer material that is widely used for microelectromechanical systems (MEMS) and has good mechanical stability and low thermal conductivity. The researchers fabricated the MHP and investigated its heating characteristics.

This is a simulation result of the temperature distribution in the proposed micro-hotplate. Credit: Toyohashi University of Technology.

Figure 1: This is a simulation result of the temperature distribution in the proposed micro-hotplate. Credit: Toyohashi University of Technology.

The first author Assistant Professor, Tatsuya Iwata, said that “By using a thick polymer film, it is possible to realize both the mechanical stability and high thermal isolation property. Furthermore, although we have to evaluate the mechanical stability, this device is promising for smart gas sensors.”

“Mechanical stability is one of the major concerns for fabricating an MHP. Using a polymer material for such microhotplates seems to be an eccentric approach, but surprisingly, it went well. Moreover, this device will boost our study to develop multimodal sensors, which are multifunctional integrated sensors including gas sensors,” said Professor Kazuaki Sawada.

The fabricated MHP consists of a heating membrane with an area of 140 μm × 140 μm, and a 33-μm-thick SU-8 layer deposited on its bridges. The simulation confirmed that the MHP displayed good thermal isolation properties (Fig. 1). The MHP temperature was found to reach 550 °C at 5V. Moreover, the power consumption of the MHP approximately corresponded to 13.9 mW for heating to 300 °C, which is comparable with the power consumption reported in the previous studies. Furthermore, a stable operation under a constant voltage was observed for 100 min.

Owing to the thick SU-8 layer, the MHP does not need the strict control of the stress that occurs inside the membrane during the fabrication process. This feature, together with the good thermal isolation property, enables the flexible layout design of the chip, and therefore, the MHP is beneficial to a miniature smart gas sensor chip. The researchers will advance their study to realize such smart gas sensors.

A group of researchers at Waseda University has developed processes and materials for ultrathin stick-on electronic devices using elastomeric “nanosheet” film, achieving ease of production while also preserving high elasticity and flexibility fifty times better than previously reported polymer nanosheets.

This is a sandwich of printed circuits and SBS elastomer is just 750 nm thick, for extremely high flexibility and comfort. Credit: Waseda University

This is a sandwich of printed circuits and SBS elastomer is just 750 nm thick, for extremely high flexibility and comfort. Credit: Waseda University

This research is published in the Journal of Materials Chemistry C online edition, February 1, 2017.

Smart electronics and wearable devices have several requirements for widespread adoption, especially ease of fabrication and wearing comfort. The materials and processes developed by the Waseda University team represent huge strides forward in both criteria.

Inkjet printing of circuitry and low-temperature fixing allow production of electronic devices which are durable and functional but also extremely thin and flexible enough for use as a comfortable, skin-fitting appliance, while also maintaining the easy handling properties and protection of elastomeric films. At only 750 nm, the new film is ultra-thin and flexible. These advances could help change the nature of wearable electronics from objects like wristwatches to items less noticeable than a band-aid.

The Waseda team also established a method of joining electronic components without soldering, allowing thinner and more flexible elastomer films (SBS: polystyrene-polybutadiene-polystyrene). Conductive “wiring” is created by inkjet printing, which can be done with a household type printer without the need for clean room conditions. Further, conductive lines and elements such as chips and LEDs are connected by adhesive sandwiching between two elastomeric nanosheets, without using chemical bonding by soldering or special conductive adhesives.

Thanks to the simple, low-temperature processes, the resulting ultrathin structures achieve better adhesion, without using adhesive matter such as tape or glue, better elasticity and comfort for skin-contact applications. The new system was proven functional for several days on an artificial skin model.

These results were achieved through collaboration among three specialties: Molecular assembly and biomaterials science; medical robotics and rehabilitation engineering; and micro-electromechanical systems, thanks to collaborative structures at Waseda University.

Uses for these products are expected to include human-machine interfaces and sensors in the form of electronic tattoos, as radically improved tools for the fields of medicine, healthcare and sports training.

These applications are the subject of further investigation by the Waseda University Institute of Advanced Active Aging Research.