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In even the most fuel-efficient cars, about 60 percent of the total energy of gasoline is lost through heat in the exhaust pipe and radiator. To combat this, researchers are developing new thermoelectic materials that can convert heat into electricity. These semiconducting materials could recirculate electricity back into the vehicle and improve fuel efficiency by up to 5 percent.

The challenge is, current thermoelectric materials for waste heat recovery are very expensive and time consuming to develop. One of the state of the art materials, made from a combination of hafnium and zirconium (elements most commonly used in nuclear reactors), took 15 years from its initial discovery to optimized performance.

Now, researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed an algorithm that can discover and optimize these materials in a matter of months, relying on solving quantum mechanical equations, without any experimental input.

“These thermoelectric systems are very complicated,” said Boris Kozinsky, a recently appointed Associate Professor of Computational Materials Science at SEAS and senior author of the paper. “Semiconducting materials need to have very specific properties to work in this system, including high electrical conductivity, high thermopower, and low thermal conductivity, so that all that heat gets converted into electricity. Our goal was to find a new material that satisfies all the important properties for thermoelectric conversion while at the same time being stable and cheap.”

Kozinsky co-authored the research with Georgy Samsonidze, a research engineer at the Robert Bosch Research and Technology Center in Cambridge, MA, where both authors conducted most of the research.

In order to find such a material, the team developed an algorithm that can predict electronic transport properties of a material based only on the chemical elements used in the crystalline crystal. The key was to simplify the computational approach for electron-phonon scattering and to speed it up by about 10,000 times, compared to existing algorithms.

The new method and computational screening results are published in Advanced Energy Materials.

Using the improved algorithm, the researchers screened many possible crystal structures, including structures that had never been synthesized before. From those, Kozinsky and Samsonidze whittled the list down to several interesting candidates. Of those candidates, the researchers did further computational optimization and sent the top performers to the experimental team.

In an earlier effort experimentalists synthesized the top candidates suggested by these computations and found a material that was as efficient and as stable as previous thermoelectric materials but 10 times cheaper. The total time from initial screening to working devices: 15 months.

“We did in 15 months of computation and experimentation what took 15 years for previous materials to be optimized,” said Kozinsky. “What’s really exciting is that we’re probably not fully understanding the extent of the simplification yet. We could potentially make this method even faster and cheaper.”

Kozinsky said he hopes to improve the new methodology and use it to explore electronic transport in a wider class of new exotic materials such as topological insulators.

The ability to harness light into an intense beam of monochromatic radiation in a laser has revolutionized the way we live and work for more than fifty years. Among its many applications are ultrafast and high-capacity data communications, manufacturing, surgery, barcode scanners, printers, self-driving technology and spectacular laser light displays. Lasers also find a home in atomic and molecular spectroscopy used in various branches of science as well as for the detection and analysis of a wide range of chemicals and biomolecules.

Lasers can be categorized based on their emission wavelength within the electromagnetic spectrum, of which visible light lasers — such as those in laser pointers — are only one small part. Infrared lasers are used for optical communications through fibers. Ultraviolet lasers are used for eye surgery. And then there are terahertz lasers, which are the subject of investigation at the research group of Sushil Kumar, an associate professor of Electrical and Computer Engineering at Lehigh University.

Left to right: Research contributors and Lehigh electrical and computer engineering graduate students Ji Chen, Liang Gao and Yuan Jin stand in the Terahertz Photonics laboratory of Sushil Kumar in the Sinclair Building at Lehigh University. Credit: Sushil Kumar, Lehigh University

Left to right: Research contributors and Lehigh electrical and computer engineering graduate students Ji Chen, Liang Gao and Yuan Jin stand in the Terahertz Photonics laboratory of Sushil Kumar in the Sinclair Building at Lehigh University. Credit: Sushil Kumar, Lehigh University

Terahertz lasers emit radiation that sits between microwaves and infrared light along the electromagnetic spectrum. Their radiation can penetrate common packaging materials such as plastics, fabrics and cardboard, and are also remarkably effective in optical sensing and analysis of a wide variety of chemicals. These lasers have the potential for use in non-destructive screening and detection of packaged explosives and illicit drugs, evaluation of pharmaceutical compounds, screening for skin cancer and even the study of star and galaxy formation.

Applications such as optical spectroscopy require the laser to emit radiation at a precise wavelength, which is most commonly achieved by implementing a technique known as “distributed-feedback.” Such devices are called single-mode lasers. Requiring single-mode operation is especially important for terahertz lasers, since their most important applications will be in terahertz spectroscopy. Terahertz lasers are still in a developmental phase and researchers around the world are trying to improve their performance characteristics to meet the conditions that would make them commercially viable.

As it propagates, terahertz radiation is absorbed by atmospheric humidity. Therefore, a key requirement for such lasers is an intense beam such that it could be used for optical sensing and analysis of substances kept at a standoff distance of several meters or more, and not be absorbed. To this end, Kumar’s research team is focused on improving their intensity and brightness, achievable in part by increasing optical power output.

In a recent paper published in the journal Nature Communications, the Lehigh team — supervised by Kumar in collaboration with Sandia National Laboratories — reported on a simple yet effective technique to enhance the power output of single-mode lasers that are “surface-emitting” (as opposed to those using an “edge-emitting” configuration). Of the two types, the surface-emitting configuration for semiconductor lasers offers distinctive advantages in how the lasers could be miniaturized, packaged and tested for commercial production.

The published research describes a new technique by which a specific type of periodicity is introduced in the laser’s optical cavity, allowing it to fundamentally radiate a good quality beam with increased radiation efficiency, thus making the laser more powerful. The authors call their scheme as having a “hybrid second- and fourth-order Bragg grating” (as opposed to a second-order Bragg grating for the typical surface-emitting laser, variations of which have been used in a wide variety of lasers for close to three decades). The authors claim that their hybrid grating scheme is not limited to terahertz lasers and could potentially improve performance of a broad class of surface-emitting semiconductor lasers that emit at different wavelengths.

The report discusses experimental results for a monolithic single-mode terahertz laser with a power output of 170 milliwatts, which is the most powerful to date for such class of lasers. The research shows conclusively that the so-called hybrid grating is able to make the laser emit at a specific desired wavelength through a simple alteration in the periodicity of imprinted grating in the laser’s cavity while maintaining its beam quality. Kumar maintains that power levels of one watt and above should be achievable with future modifications of their technique — which might just be the threshold needed to be overcome for industry to take notice and step into potential commercialization of terahertz laser-based instruments.

 

Graphene has many properties; it is e.g. an extremely good conductor. But it does not absorb light very well. To remedy this limiting aspect of what is an otherwise amazing material, physicists resort to embedding a sheet of graphene in a flat photonic crystal, which is excellent for controlling the flow of light. The combination endows graphene with substantially enhanced light-absorbing capabilities. In a new study published in EPJ B, Arezou Rashidi and Abdolrahman Namdar from the University of Tabriz, Iran demonstrate that, by altering the temperature in such a hybrid cavity structure, they can tune its capacity for optical absorption. They explain that it is the thermal expansion and thermo-optical effects which give the graphene these optical characteristics. Potential applications include light sensors, ultra-fast lasers, and systems capable of modulating incoming optical beams.

The authors study the light absorption of the material as a function of temperature, the chemical energy potential, the light polarisation and its incidence angles. To do so, they use a modelling method called the transfer matrix method. They find that for normal light incidence, there is enhanced absorption at room temperature, while the absorption peak is shifted toward the red as the temperature increases.

Absorption on the plane of incident angle and wavelength. Credit: Springer

Absorption on the plane of incident angle and wavelength. Credit: Springer

As light comes in at an angle, the authors show that the absorption peaks are sensitive to the incident angles as well as the polarisation state of the light. They also find that by increasing the incident angle, the peak wavelength is shifted toward the blue.

They conclude that the peak wavelength can be controlled by varying either the temperature or incident angle, as well as the chemical energy potential of graphene. This shows that there are a number of tunable features that could be exploited for the design of graphene-based nano-devices, such as temperature-sensitive absorbers and sensors.

Japanese researchers have developed a new method to build large areas of semiconductive material that is just two molecules thick and a total of 4.4 nanometers tall. The films function as thin film transistors, and have potential future applications in flexible electronics or chemical detectors. These thin film transistors are the first example of semiconductive single molecular bilayers created with liquid solution processing, a standard manufacturing process that minimizes costs.

Top surface view of 3-D computer model (left) and Atomic Force Microscopy image (right) of the new film made by University of Tokyo scientists. The well-organized structure of the molecules is visible in both the 3-D computer model and microscope image as a herringbone or cross-hair pattern. The color differences in the microscopy image are a result of the different lengths of the molecules' tails; the length differences cause the geometric frustration that prevents layers from stacking. pm = picometers, nm = nanometers. Credit: Shunto Arai and Tatsuo Hasegawa

Top surface view of 3-D computer model (left) and Atomic Force Microscopy image (right) of the new film made by University of Tokyo scientists. The well-organized structure of the molecules is visible in both the 3-D computer model and microscope image as a herringbone or cross-hair pattern. The color differences in the microscopy image are a result of the different lengths of the molecules’ tails; the length differences cause the geometric frustration that prevents layers from stacking. pm = picometers, nm = nanometers. Credit: Shunto Arai and Tatsuo Hasegawa

“We want to give electronic devices the features of real cell membranes: flexible, strong, sensitive, and super thin. We found a novel way to design semiconductive single molecular bilayers that allows us to manufacture large surface areas, up to 100 square centimeters (39 square inches). They can function as high performance thin film transistors and could have many applications in the future,” said Assistant Professor Shunto Arai, the first author on the recent research publication.

Professor Tatsuo Hasegawa of the University of Tokyo Department of Applied Physics led the team that built the new film. The breakthrough responsible for their success is a concept called geometric frustration, which uses a molecular shape that makes it difficult for molecules to settle in multiple layers on top of each other.

The film is transparent, but the forces of attraction and repulsion between the molecules create an organized, repeated herringbone pattern when the film is viewed from above through a microscope. The overall molecular structure of the bilayer is highly stable. Researchers believe it should be possible to build the same structure out of different molecules with different functionalities.

The individual molecules used in the current film are divided into two regions: a head and a tail. The head of one molecule stacks on top of another, with their tails pointing in opposite directions so the molecules form a vertical line. These two molecules are surrounded by identical head-to-head pairs of molecules, which all together form a sandwich called a molecular bilayer.

Researchers discovered they could prevent additional bilayers from stacking on top by building the bilayer out of molecules with different length tails, so the surfaces of the bilayer are rough and naturally discourage stacking. This effect of different lengths is referred to as geometric frustration.

Standard methods of creating semiconductive molecular bilayers cannot control the thickness without causing cracks or an irregular surface. The geometric frustration of different length tails has allowed researchers to avoid these pitfalls and build a 10cm by 10cm (3.9 inches by 3.9 inches) square of their film using the common industrial method of solution processing.

The semiconductive properties of the bilayer may give the films applications in flexible electronics or chemical detection.

Semiconductors are able to switch between states that allow electricity to flow (conductors) and states that prevent electricity from flowing (insulators). This on-off switching is what allows transistors to quickly change displayed images, such as a picture on an LCD screen. The single molecular bilayer created by the UTokyo team is much faster than amorphous silicon thin film transistors, a common type of semiconductor currently used in electronics.

The team will continue to investigate the properties of geometrically frustrated single molecular bilayers and potential applications for chemical detection. Collaborators based at the National Institute of Advanced Industrial Science and Technology, the Nippon Kayaku Company Limited, Condensed Matter Research Center, and High Energy Accelerator Research Organization also contributed to the research.

STMicroelectronics (NYSE:STM), a global semiconductor leader serving customers across the spectrum of electronics applications, and Jorjin Technologies Inc., a Taipei, Taiwan based company established in 1997 to design and supply modules worldwide, today announced the certification of the dual-radio modules that combine Sigfox wireless-network technology with Bluetooth low energy (BLE).

Jorjin’s WS211x Sigfox/BLE modules benefit from the market-leading performance and energy efficiency of ST’s BlueNRG-1 BLE System-on-Chip (SoC) and the S2-LP sub-1GHz RF transceiver. These advantages have enabled Jorjin’s modules to deliver cutting-edge connectivity and great battery lifetime, targeting coin-cell -operated or energy-harvesting IoT applications.

Fully programmable devices, Jorjin’s new Sigfox modules exploit the ultra-low power Arm® Cortex®-M0 technology embedded in ST’s BLE SoC to act as independent IoT connectivity nodes. The combination of BLE with Sigfox’ low-power wide-area network (LPWAN) provides key benefits to IoT systems, such as firmware update over-the-air, which is not possible with conventional ‘Sigfox-only’ modules. Other benefits of having an IoT device connected both remotely through the Sigfox network and locally through BLE include the possibility to modify device settings during installation or maintenance, or to trace assets, which often change their position inside an area covered with BLE beacon stations.

“We are excited to achieve certification for our first Sigfox-compatible modules,” said Jorjin Technologies chairman Tom Liang. “STMicroelectronics and Sigfox teams’ support has been very helpful and we are looking forward to keeping expanding our collaboration with both partners.”

“The successful certification marks a significant milestone in our cooperation with Jorjin, delivering high-performance, ultra-low-power dual-radio Sigfox modules,” said Maria Rosa Borghi, Low Power RF BU Senior Director, Analog, MEMS and Sensors Group, STMicroelectronics. “Designers now get a cutting-edge solution for building high-mobility products with versatile connectivity and low power budget across all IoT segments.”

“We are glad to welcome Jorjin to our ever-expanding ecosystem and to partner once again with ST for the acceleration of the adoption of the IoT among the different verticals. The certification of the Jorjin module will allow us to boost the production of Sigfox-enabled devices answering a growing demand from our clients,” said Raouti Chehih, Sigfox Chief Adoption Officer.

The evaluation board for the WS211x modules uses the Arduino interface to ease customer development and is compatible with ST’s Arduino shield boards featuring MEMS motion sensors, environmental sensors, or Time-of-Flight (ToF) ranging sensors. An SDK is available from Jorjin enabling customers to develop applications using WS211x modules with ST’s sensor shield boards, as well as an AT command list facilitating customers test of the modules’ BLE and Sigfox functions.

Cheap, flexible and sustainable plastic semiconductors will soon be a reality thanks to a breakthrough by chemists at the University of Waterloo.

Professor Derek Schipper and his team at Waterloo have developed a way to make conjugated polymers, plastics that conduct electricity like metals, using a simple dehydration reaction the only byproduct of which is water.

“Nature has been using this reaction for billions of years and industry more than a hundred,” said Schipper, a professor of Chemistry and a Canada Research Chair in Organic Material Synthesis. “It’s one of the cheapest and most environmentally friendly reactions for producing plastics.”

Schipper and his team have successfully applied this reaction to create poly(hetero)arenes, one of the most studied classes of conjugated polymers which have been used to make lightweight, low- cost electronics such as solar cells, LED displays, and chemical and biochemical sensors.

Dehydration is a common method to make polymers, a chain of repeating molecules or monomers that link up like a train. Nature uses the dehydration reaction to make complex sugars from glucose, as well as proteins and other biological building blocks such as cellulose. Plastics manufacturers use it to make everything from nylon to polyester, cheaply and in mind-boggling bulk.

“Synthesis has been a long-standing problem in this field,” said Schipper. “A dehydration method such as ours will streamline the entire process from discovery of new derivatives to commercial product development. Better still, the reaction proceeds relatively fast and at room temperature.”

Conjugated polymers were first discovered by Alan Heeger, Alan McDonald, and Hideki Shirakawa in the late 1970s, eventually earning them the Nobel Prize in Chemistry in 2000.

Researchers and engineers quickly discovered several new polymer classes with plenty of commercial applications, including a semiconducting version of the material; but progress has stalled in reaching markets in large part because conjugated polymers are so hard to make. The multi-step reactions often involve expensive catalysts and produce environmentally harmful waste products.

Schipper and his team are continuing to perfect the technique while also working on developing dehydration synthesis methods for other classes of conjugated polymers. The results of their research so far appeared recently in the journal Chemistry – A European Journal.

 

The next generation of energy-efficient power electronics, high-frequency communication systems, and solid-state lighting rely on materials known as wide bandgap semiconductors. Circuits based on these materials can operate at much higher power densities and with lower power losses than silicon-based circuits. These materials have enabled a revolution in LED lighting, which led to the 2014 Nobel Prize in physics.

In new experiments reported in Applied Physics Letters, from AIP Publishing, researchers have shown that a wide-bandgap semiconductor called gallium oxide (Ga2O3) can be engineered into nanometer-scale structures that allow electrons to move much faster within the crystal structure. With electrons that move with such ease, Ga2O3 could be a promising material for applications such as high-frequency communication systems and energy-efficient power electronics.

Schematic stack and the scanning electron microscopic image of the β-(AlxGa1-x)2O3/Ga2O3 modulation-doped field effect transistor. Credit: Choong Hee Lee and Yuewei Zhang

Schematic stack and the scanning electron microscopic image of the β-(AlxGa1-x)2O3/Ga2O3 modulation-doped field effect transistor. Credit: Choong Hee Lee and Yuewei Zhang

“Gallium oxide has the potential to enable transistors that would surpass current technology,” said Siddharth Rajan of Ohio State University, who led the research.

Because Ga2O3 has one of the largest bandgaps (the energy needed to excite an electron so that it’s conductive) of the wide bandgap materials being developed as alternatives to silicon, it’s especially useful for high-power and high-frequency devices. It’s also unique among wide bandgap semiconductors in that it can be produced directly from its molten form, which enables large-scale manufacturing of high-quality crystals.

For use in electronic devices, the electrons in the material must be able to move easily under an electric field, a property called high electron mobility. “That’s a key parameter for any device,” Rajan said. Normally, to populate a semiconductor with electrons, the material is doped with other elements. The problem, however, is that the dopants also scatter electrons, limiting the electron mobility of the material.

To solve this problem, the researchers used a technique known as modulation doping. The approach was first developed in 1979 by Takashi Mimura to create a gallium arsenide high-electron mobility transistor, which won the Kyoto Prize in 2017. While it is now a commonly used technique to achieve high mobility, its application to Ga2O3 is something new.

In their work, the researchers created a so-called semiconductor heterostructure, creating an atomically perfect interface between Ga2O3 and its alloy with aluminum, aluminum gallium oxide — two semiconductors with the same crystal structure but different energy gaps. A few nanometers away from the interface, embedded inside the aluminum gallium oxide, is a sheet of electron-donating impurities only a few atoms thick. The donated electrons transfer into the Ga2O3, forming a 2-D electron gas. But because the electrons are now also separated from the dopants (hence the term modulation doping) in the aluminum gallium oxide by a few nanometers, they scatter much less and remain highly mobile.

Using this technique, the researchers reached record mobilities. The researchers were also able to observe Shubnikov-de Haas oscillations, a quantum phenomenon in which increasing the strength of an external magnetic field causes the resistance of the material to oscillate. These oscillations confirm formation of the high mobility 2-D electron gas and allow the researchers to measure critical material properties.

Rajan explained that such modulation-doped structures could lead to a new class of quantum structures and electronics that harnesses the potential of Ga2O3.

Sensera Inc. (MicroDevices) has acquired and qualified a SPTS ASE-HRM etch platform. This etcher adds capability to the fab that was previously outsourced to partners. This is a key process technology development tool to bring complex MicroElectroMechanical Systems (MEMS) to market.

This system offers market leading etch rates while controlling ion damage through a de-coupled plasma source. The HRM is ideal for deep anisotropic silicon etching at high rates with the STS ASE process. This technology eliminates sidewall breakdown, which results in enhanced process performance and a high device yield.

“We are very pleased to bring to our customers additional Deep Reactive Ion Etch (DRIE) capabilities. This equipment supplements Sensera’s existing etch tool set and enables increased throughput and improved etch uniformity to meet our customers’ rapidly growing demand,” said Tim Stucchi, COO of Sensera’s MicroDevices division.

“ClassOne Equipment was happy to provide this advanced etch platform to Sensera. We have worked with many etch platforms and the SPTS ASE-HRM delivers excellent etch performance with a low cost of ownership. ClassOne maintains a close partnership with our customers and is proud of a long history of customer satisfaction. This is our second installation at Sensera, and we recently took the first steps in a new project, look for more exciting news later this year,” said Byron Exarcos, CEO of ClassOne Equipment.

“We continue to add new capabilities to our fab in order to drive down cycle time, control quality and improve costs,” stated Ralph Schmitt, CEO of Sensera Inc. “These are important steps as we move many of our customers to commercial volume shipments. This is all part of the strategy of the company to have internal capability to develop complex MEMS.”

In a recent study published in Science, researchers at ICFO – The Institute of Photonic Sciences in Barcelona, Spain, along with other members of the Graphene Flagship, reached the ultimate level of light confinement. They have been able to confine light down to a space one atom, the smallest possible. This will pave the way to ultra-small optical switches, detectors and sensors.

Light can function as an ultra-fast communication channel, for example between different sections of a computer chip, but it can also be used for ultra-sensitive sensors or on-chip nanoscale lasers. There is currently much research into how to further shrink devices that control and guide light.

New techniques searching for ways to confine light into extremely tiny spaces, much smaller than current ones, have been on the rise. Researchers had previously found that metals can compress light below the wavelength-scale (diffraction limit), but more confinement would always come at the cost of more energy loss. This fundamental issue has now been overcome.

“Graphene keeps surprising us: nobody thought that confining light to the one-atom limit would be possible. It will open a completely new set of applications, such as optical communications and sensing at a scale below one nanometer,” said ICREA Professor Frank Koppens at ICFO – The Institute of Photonic Sciences in Barcelona, Spain, who led the research.

This team of researchers including those from ICFO (Spain), University of Minho (Portugal) and MIT (USA) used stacks of two-dimensional materials, called heterostructures, to build up a new nano-optical device. They took a graphene monolayer (which acts as a semi-metal), and stacked onto it a hexagonal boron nitride (hBN) monolayer (an insulator), and on top of this deposited an array of metallic rods. They used graphene because it can guide light in the form of plasmons, which are oscillations of the electrons, interacting strongly with light.

“At first we were looking for a new way to excite graphene plasmons. On the way, we found that the confinement was stronger than before and the additional losses minimal. So we decided to go to the one atom limit with surprising results,” said David Alcaraz Iranzo, the lead author from ICFO.

By sending infra-red light through their devices, the researchers observed how the plasmons propagated in between the metal and the graphene. To reach the smallest space conceivable, they decided to reduce the gap between the metal and graphene as much as possible to see if the confinement of light remained efficient, i.e. without additional energy losses. Strikingly, they saw that even when a monolayer of hBN was used as a spacer, the plasmons were still excited, and could propagate freely while being confined to a channel of just one atom thick. They managed to switch this plasmon propagation on and off, simply by applying an electrical voltage, demonstrating the control of light guided in channels smaller than one nanometer.

This enables new opto-electronic devices that are just one nanometer thick, such as ultra-small optical switches, detectors and sensors. Due to the paradigm shift in optical field confinement, extreme light-matter interactions can now be explored that were not accessible before. The atom-scale toolbox of two-dimensional materials has now also proven applicable for many types of new devices where both light and electrons can be controlled even down to the scale of a nanometer.

Professor Andrea C. Ferrari, Science and Technology Officer of the Graphene Flagship, and Chair of its Management Panel, added “While the flagship is driving the development of novel applications, in particular in the field of photonics and optoelectronics, we do not lose sight of fundamental research. The impressive results reported in this paper are a testimony to the relevance for cutting edge science of the Flagship work. Having reached the ultimate limit of light confinement could lead to new devices with unprecedented small dimensions.”

Mobile Semiconductor, a Seattle WA based company, today announced the inclusion of its new 22nm ULL (Ultra Low Leakage) memory compilers in the industry leading GLOBALFOUNDRIES FDXcelerator Program.  This new embedded SRAM technology on 22nm FDX offers the best in class memory solution using the GLOBALFOUNDRIES low leakage FDSOI bit cells and ultra-low leakage devices.

Cameron Fisher, CEO and Founder of Mobile Semiconductor, said, “This is a very important technology for low cost industrial and consumer products.  Our customers come from a wide range of markets, but one thing they share in common is the need to drive the power usage down to allow maximum battery life.”

This new compiler, equipped with multiple speed grades, allows the customer to maximize performance of their end product balancing power vs speed.  These low leakage memories make intelligent use of the reverse body bias capabilities of the FDSOI technology to control leakage and enhance performance.

Mobile Semiconductor’s 22nm ULL memory complier is unique in the industry and comes with the same high-quality design, testing, and support that customers have come to expect from their products.

Fisher said, “Mobile Semiconductor remains the leader in providing low power solutions and this complier removes the roadblocks that engineers have struggled with in their previous designs. Almost every single product developed for the IoT Market, will have new and more stringent demands placed on them.  We believe that Mobile Semiconductor is meeting the most important one – power!”