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Multibeam Corporation today disclosed a new patent that describes the innovative use of e-beam technology for highly localized precision etching in manufacturing advanced memory and logic ICs. The vast improvement enabled by the new patent highlights the company’s leadership in innovating a high-throughput e-beam platform to enhance the industry’s fabrication capability.

Multibeam’s dynamic e-beam platform concurrently addresses four major applications: Complementary E-Beam Lithography (CEBL) to reduce litho cost; Direct Electron Writing (DEW) to enhance device security; Direct Deposition/Etch (DDE) for highly localized precision etch and deposition using directed electron activation; and E-Beam Inspection (EBI) to speed defect detection and yield ramp.

The new patent describes innovative techniques utilizing electrons to enhance selective removal of material from the substrate at precise locations. The techniques are especially useful for advanced-IC fabrication.

The electrons deliver incremental activation energy to initiate chemical reactions on the wafer surface in the plasma, while leveraging existing etch chemistry. The electrons are directed to exact locations in accordance with the layout database, eliminating optical patterning (including multi-patterning) and masks. The electron-enhancement techniques reduce cost and complexity while complementing conventional plasma etching.

The etch process is further enhanced by innovative kinetic lens technology described in the patent. Each e-beam column is augmented with a gas “lens” that increases local partial pressure of select gas components to accelerate desired chemical reactions. The gas lens also eliminates gas-purge cycles to increase throughput.

A photon lens focuses on the etch target to modulate gas adsorption rate and speed etching. The photon lenses can also act as detectors to ensure precision process monitoring and control.

Each e-beam in the multi-column array is individually controlled. Multiple e-beam process chambers can be integrated into a cluster tool for higher throughput.

Complementary E-Beam technology

Multibeam’s expanding IP portfolio in advanced chip-making and device-security applications seeks to complement and enhance established technology solutions, not to supplant them. Electrons have different properties than the photons used in conventional optical lithography. The e-beam can be controlled directly from a database with no need for masks. Multibeam’s proprietary mini-column makes the process chamber compact and small, enabling multi-chamber clustering to boost throughput. The company’s complementary e-beam technology promises to extend IC fabrication capability, benefiting both semiconductor device manufacturers and their customers.

Multibeam Corporation is a leading electron-beam technology innovator in wafer fab equipment.

A team of Russian, Czech and German researchers gained a new perspective on the properties of three materials of biological origin. Besides two reference materials with well-studied properties — serum albumin and cytochrome C — the researchers looked at the extracellular matrix of the Shewanella oneidensis MR-1 bacterium, which is used in biofuel cells. The team measured the materials’ dynamic conductivity and dielectric permittivity in a wide range of frequencies and temperatures. To interpret their findings, the researchers used theoretical approaches and concepts from condensed matter physics. The paper detailing the study was published in the journal Scientific Reports.

“So far, the formalism of condensed matter physics has only found limited use in classical biochemistry and biophysics. As a result, certain interesting effects evade our attention,” says Konstantin Motovilov, senior research scientist at the Laboratory of Terahertz Spectroscopy at Moscow Institute of Physics and Technology (MIPT). “When we do make use of this language, we acquire new ways of modeling observed phenomena and describing biological structures. In our paper, we characterize the behavior of proteins, considered as classical amorphous semiconductors, with the help of the formalism of condensed matter physics.”

Before discussing the study, here is a quick example of how solid-state physics explains the electrical properties of different materials.

There are in fact multiple mechanisms of electrical conductivity. For each, there is a corresponding theory that describes the properties of certain materials. For example, the conductivity in metals is adequately explained by the Drude theory. In the theory, there is no interaction between the conduction electrons, which are assumed to only occasionally collide with crystal lattice, impurities, and defects. Electrical conductivity is the inverse of electrical resistivity. Conductivity indicates how easy it is for an electric current to pass through a given material. Within the Drude model, this property does not depend strongly on frequency up to the frequency of the collisions between charge carriers and lattice or impurities. However, there is a large group of conductive materials that do not fit this description. Yet their behavior in an external electromagnetic field is quite interesting. Among them are glasses, ionic conductors, and amorphous semiconductors.

To qualitatively describe the electrical properties of such materials, another theory was proposed about 40 years ago by Andrzej Karol Jonscher, an English physicist. According to his theory, charge carriers — electrons, for example — can adequately be considered as free at room temperature, provided the alternating current frequency does not exceed several megahertz. Under these conditions, the Drude model is applicable and conductivity is nearly constant, i.e., it does not depend on the frequency of the external field. If, however, the frequency is higher, this description is no longer valid and there is an increase in conductivity proportional to a certain power — which is close to 0.8 — of frequency. The same effect is observed for materials that are gradually cooled, even if the frequency is kept constant.

Interestingly, different materials exhibit quite similar behavior in that regard. Moreover, if you restate the dependences — say, talk about the ratio between direct current (static) conductivity and alternating current conductivity, as opposed to conductivity as such — the relations for all materials turn out to be identical, revealing the so-called Universal Dielectric Response (UDR). This curious phenomenon was thoroughly investigated in a study that examined the conduction in glasses and other amorphous materials, offering new insights into their structure and properties.

The authors of the paper showed that Jonscher’s law for conductivity applies to three organic materials. Among them, two are well-known reference proteins: bovine serum albumin and bovine heart cytochrome C. Their structural, physical, and chemical properties have been investigated in detail, so the researchers used them as reference materials.

In addition, they examined the extracellular matrix and filaments (EMF) of the Shewanella oneidensis MR-1 bacterium, which can produce electricity in biological fuel cells. S. oneidensis has been used in many studies with a focus on alternative energy sources, so its electrical properties are of interest to both researchers and engineers. In 2010, a team of researchers based in the United States and Canada showed that the bacterium’s extracellular appendages behave a lot like p-type semiconductors. The electrical properties of S. oneidensis MR-1 have nevertheless not been studied in detail. The recently published paper is an attempt to remedy that.

The authors measured the conductivity of the materials, as well as the energy losses in a frequency range from 1 hertz to 1.5 terahertz, or trillion hertz, for temperatures from -260 to 40 degrees Celsius. (Strictly speaking, the energy losses are given by the imaginary part of the complex dielectric permittivity.) Next, the researchers measured the direct current conductivity of EMF for temperatures from zero to 40 C, as well as the temperature dependence of their heat capacity. For each of the three materials, water content and ion concentration were also determined.

To do this, the researchers pressed the substances into pellets using a 1-centimeter mold. They then applied electrodes to the faces of the pellets to pass alternating current through them in order to measure the electrical conductivity and dielectric permittivity of the materials in the 1-300 million hertz range. For higher frequencies, this approach does not work, so for the 30-1,500 gigahertz, or billion hertz, range, the team obtained the spectra of complex dielectric permittivity using quasioptical terahertz spectroscopy. No measurements were made in the intermediate frequency range.

It turned out that at room temperature, EMF conductivity is nearly constant, and when the frequency is increased above several million hertz, or several megahertz, the conductivity is proportional to a certain power — which is close to 1 — of the frequency. Cytochrome C did not exhibit such behavior unless the frequency was low and the temperature high. In the case of albumin, it was not observed at all. This suggests that different conductivity mechanisms are at play in these materials. It is likely that EMF has nearly free charges at room temperature — just like in the Drude model — whereas albumin does not have them and cytochrome C is a mixed bag.

The dependence observed by the researchers can be explained in terms of the individual properties of the materials. Both cytochrome C and albumin are regular proteins. Although these materials do have some free charges, these are not nearly as many as it would be necessary to justify the Drude model. Comparing the conductivity in EMF to that in metals (conductors) is more realistic, as free charges are more easily generated in these molecules. However, a comparison even more valid would be that with a solution of table salt, which has a high concentration of free ions.

Naturally, a complete description is more complex and would require us to take the water content of materials and other factors into account. For instance, because EMF contains significant amounts of loosely bound water, its conductivity grows quadratically at temperatures of about -250 C and frequencies on the order of 100 billion hertz (sub-terahertz terahertz range). Temperatures that low cause the bulk water in the material to freeze, and high frequencies mean that the dielectric properties resulting from water dipole dynamics become non-negligible. The other materials, too, exhibit deviations from Jonscher’s predictions, but they are not as dramatic.

The authors have thus clearly shown the powerful methodology and instrumentation of condensed matter physics to be effective for fundamental research into the electrodynamics of biological objects. The next step could involve the application to biomaterials research of the wide range of other theories and models that have been effectively used by the physics community for many decades.

Semtech Corporation (Nasdaq:SMTC), a supplier of high performance analog and mixed-signal semiconductors and advanced algorithms, announced its next generation LoRa devices and wireless radio frequency (RF) technology (LoRa Technology) chipsets enabling innovative LPWAN use cases for consumers with its advanced technology. Addressing the need for cost-effective and reliable sensor-to-cloud connectivity in any type of RF environment, the new features and capabilities will significantly improve the performance and capability of Internet of Things (IoT) sensor applications that demand ultra-low power, small form factor and long range wireless connectivity with a shortened product development cycle.

The next generation LoRa radios extends Semtech’s link budget by 20% with a 50% reduction in receiver current (4.5 mA) and a high power +22 dBm option. This extends battery life of LoRa-based sensors up to 30%, which reduces the frequency of battery replacement. The extended connectivity range, with the ability to reach deep indoor and outdoor sensor locations, will create new markets as different types of verticals integrate LoRa Technology in their IoT applications including healthcare and pharmaceuticals, media and advertising, logistics/shipping, and asset tracking.

In addition, the new platform has a command interface that simplifies radio configuration and shortens the development cycle, needing only 10 lines of code to transmit or receive a packet, which will allow users to focus on applications. The small footprint, 45% less than the current generation, is highly configurable to meet different application requirements utilizing the global LoRaWAN open standard. The chipsets also supports FSK modulation to allow compatibility with legacy protocols that are migrating to the LoRaWAN™ open protocol for all the performance benefits LoRa Technology provides.

“LPWAN IoT applications are going through a massive transformation, shifting from trials to large deployments in smart cities, buildings, healthcare, logistics, and agriculture,” said Marc Pegulu, Vice President and General Manager for Semtech’s Wireless and Sensing Products Group. “LoRa Technology enables an infinite amount of IoT use cases as Semtech pushes for the last mile of connectivity and reinforces its position as the defacto platform for LPWAN.”

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Spontaneous polarization appears to be parallel with the c-axis, while spontaneous magnetism appears to be parallel with the a-axis. Credit: None

Spontaneous polarization appears to be parallel with the c-axis, while spontaneous magnetism appears to be parallel with the a-axis. Credit: None

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as magnetic (electric) field-controlled ferroelectric (ferromagnetic) properties and because they can be used in novel technological applications such as fast-writing, power-saving, and nondestructive data storage. However, because multiferroicity is typically observed at low temperatures, it is highly desirable to develop multiferroic materials that can be observed at room temperature.

GaxFe2-xO3, or GFO for short, is a promising room-temperature multiferroic material because of its large magnetization. GFO thin films have already been successfully fabricated, and their polarization switching at room temperature has been demonstrated. However, their ferroelectric and ferromagnetic properties must be controlled to realize better magnetoelectric properties and applications of GFO films. In order to control these properties, it is essential to understand the relationship between the constituent composition at each cation site and the original character.

Therefore, the research team led by Mitsuru Ito at Tokyo Tech set out to systematically investigate multiferroicity as a function of the compositional ratio of Ga and Fe in GFO films. Specifically, they studied the ferroelectric properties of the GFO films using piezoresponse force microscopy, and found that GaxFe2-xO3 films with x = 1 and 0.6 show ferroelectricity at room temperature. The piezoresponse phase can be reversed by 180° when a voltage of more than 4.5 V is applied. This behavior is typical of ferroelectric materials and is a strong indicator of the presence of switchable polarization in the film at room temperature.

The scientists also confirmed room-temperature ferrimagnetism of the films through magnetic characterization. Lastly, they were able to demonstrate the room-temperature magnetocapacitance effects of the GFO films. They reported that by changing x, the coercive electric field, coercive force, and saturated magnetism values could be controlled. They also showed that the ferroelectric and magnetic ranges of GFO-type iron oxides differ from those of the well-known room-temperature multiferroic BiFeO2 and may expand the variety of room-temperature multiferroic materials.

A team of physicists, headed by the U.S. Naval Research Laboratory (NRL), have demonstrated the means to improve the optical loss characteristics and transmission efficiency of hexagonal boron nitride devices, enabling very small lasers and nanoscale optics.

Image shows directly measured polaritons propagating through a flake of Hexagonal boron nitride (hBN). This material has been identified as an ideal substrate for two-dimensional materials research while also recently being demonstrated as an exciting optical material for infrared nanophotonics. Credit: (US Naval Research Laboratory)

Image shows directly measured polaritons propagating through a flake of Hexagonal boron nitride (hBN). This material has been identified as an ideal substrate for two-dimensional materials research while also recently being demonstrated as an exciting optical material for infrared nanophotonics. Credit: (US Naval Research Laboratory)

“The applications for this research are considerably broad,” said Dr. Alexander J. Giles, research physicist, NRL Electronics Science and Technology Division. “By confining light to very small dimensions, nanophotonic devices have direct applications for use in ultra-high resolution microscopes, solar energy harvesting, optical computing and targeted medical therapies.”

Hexagonal boron nitride (hBN) forms an atomically thin lattice consisting of boron and nitrogen atoms. This material has recently been demonstrated as an exciting optical material for infrared nanophotonics and is considered an ‘ideal substrate’ for two-dimensional materials.

While previous work demonstrated that natural hBN supports deeply sub-diffractional hyperbolic phonon polaritons desired for applications, such as, sub-diffractional optical imaging (so-called ‘hyperlensing’), energy conversion, chemical sensing, and quantum nanophotonics, limited transmission efficiencies continue to persist.

“We have demonstrated that the inherent efficiency limitations of nanophotonics can be overcome through the careful engineering of isotopes in polar semiconductors and dielectric materials,” Giles said.

Naturally occurring boron is comprised of two isotopes, boron-10 and boron-11, lending a 10 percent difference in atomic masses. This difference results in substantial losses due to phonon scattering, limiting the potential applications of this material. The research team at NRL has engineered greater than 99 percent isotopically pure samples of hBN, meaning they consist almost entirely of either boron-10 or boron-11 isotopes.

This approach results in a dramatic reduction in optical losses, resulting in optical modes that travel up to three times farther and persist for up to three times longer than natural hBN. These long-lived vibrational modes not only enable immediate advances specific to hBN – near field optics and chemical sensing – but also provide a strategic approach for other materials systems to exploit and build upon.

“Controlling and manipulating light at nanoscale, sub-diffractional dimensions is notoriously difficult and inefficient,” said Giles. “Our work represents a new path forward for the next generation of materials and devices.”

From the Internet of Things to the cloud to artificial intelligence, industries are seeing a new wave of technologies that have the potential to transform and significantly impact the world around us. For its latest white paper, business information provider IHS Markit (Nasdaq: INFO) surveyed its leading technology experts to find out how these technologies are coming together in new and powerful ways to fundamentally change businesses, fuel innovation, disrupt industries and create both threats and opportunities.

The top eight transformative technologies for the global technology market in 2018, as identified in the IHS Markit report, are as follows:

Trend #1: Artificial intelligence (AI)

AI has matured to the point where it is being used as a competitive differentiator in several industries, particularly in the smartphone, automotive and medical markets. Also, optimization for on-device versus cloud-based solutions is becoming an area of focus. Cloud AI has more computing power to analyze data as it utilizes deep learning algorithms, but there are potential issues around privacy, latency and stability. On-device AI, meanwhile, can help offset those dangers to some degree. For instance, smartphone users who deploy the built-in AI of their phones are able to store data locally and thus safeguard their privacy.

Trend #2: Internet of Things (IoT)

The global installed base of IoT devices will rise to 73 billion in 2025, IHS Markit forecasts show. Accelerating IoT growth in 2018 and movement through a four-stage IoT evolution — “Connect, Collect, Compute and Create” — will be the confluence of enhanced connectivity options with edge computing and cloud analytics.

Enhancements in IoT connectivity, such as low-power wireless access (LPWA) will drive growth. Moreover, technologies adjacent to the IoT will become increasingly sophisticated. Machine video and ubiquitous video will empower new types of visual analytics. And AI, the cloud and virtualization will help develop critical insights sourced from data at the so-called “edge” of computing networks. Applying AI techniques to data will drive monetization in the form of cost savings, greater efficiencies and a transition from product- to service-centric business models.

Trend #3: Cloud and virtualization

Cloud services will pave the way for technologically immature companies to utilize machine learning (ML) and AI, radically transforming their usage and understanding of data.

Trend #4: Connectivity

As the first 5G commercial deployments emerge, the story will focus on connectivity. However, the path to full 5G adoption and deployment is complicated, with new opportunities and challenges alike in store for mobile network operators, infrastructure providers, device manufacturers and end users. 5G represents a dramatic expansion of traditional cellular technology use cases beyond mobile voice and broadband, to include a multitude of IoT and mission-critical applications.

Trend #5: Ubiquitous video

The growing use of screens and cameras across multiple consumer- and enterprise-device categories, along with increasingly advanced broadcast, fixed and mobile data networks, is powering an explosion in video consumption, creation, distribution and data traffic. More importantly, video content is increasingly expanding beyond entertainment into industrial applications for medical, education, security and remote controls, as well as digital signage.

Trend #6: Computer vision

The increasing importance of computer vision is directly tied to the mega-trend of digitization that has been playing out in the industrial, enterprise and consumer segments. The proliferation of image sensors, as well as improvements in image processing and analysis, are enabling a broad range of applications and use cases including industrial robots, drone applications, intelligent transportation systems, high-quality surveillance, and medical and automotive.

Trend #7: Robots and drones

The global market for robots and drones will grow to $3.9 billion in 2018. The deeper underpinnings of the story, however, lie in the disruptive potential of robots and drones to transform long-standing business models in manufacturing and industry, impacting critical areas such as logistics, material picking and handling, navigational autonomy and delivery.

Trend #8: Blockchain

Blockchain enables decentralized transactions and is the underlying technology for digital currency such as bitcoin and ether. Blockchain-based services beyond financial services are already being developed and deployed and will continue to ramp in 2018. These include: the use of blockchain to improve advertising measurement and combat ad fraud; blockchain-based systems for distributing music royalty payments; and solutions to better track and manage electronics supply chains.

Carbon nanotubes bound for electronics need to be as clean as possible to maximize their utility in next-generation nanoscale devices, and scientists at Rice and Swansea universities have found a way to remove contaminants from the nanotubes.

Rice chemist Andrew Barron, also a professor at Swansea in the United Kingdom, and his team have figured out how to get nanotubes clean and in the process discovered why the electrical properties of nanotubes have historically been so difficult to measure.

Scientists at Rice and Swansea universities have demonstrated that heating carbon nanotubes at high temperatures eliminates contaminants that make nanotubes difficult to test for conductivity. They found when measurements are taken within 4 microns of each other, regions of depleted conductivity caused by contaminants overlap, which scrambles the results. The plot shows the deviation when probes test conductivity from minus 1 to 1 volt at distances greater or less than 4 microns. Credit: Barron Research Group/Rice University

Scientists at Rice and Swansea universities have demonstrated that heating carbon nanotubes at high temperatures eliminates contaminants that make nanotubes difficult to test for conductivity. They found when measurements are taken within 4 microns of each other, regions of depleted conductivity caused by contaminants overlap, which scrambles the results. The plot shows the deviation when probes test conductivity from minus 1 to 1 volt at distances greater or less than 4 microns. Credit: Barron Research Group/Rice University

Like any normal wire, semiconducting nanotubes are progressively more resistant to current along their length. But over the years, conductivity measurements of nanotubes have been anything but consistent. The Rice-Swansea team wanted to know why.

“We are interested in the creation of nanotube-based conductors, and while people have been able to make wires, their conduction has not met expectations,” Barron said. “We wanted to determine the basic science behind the variability observed by other researchers.”

They discovered that hard-to-remove contaminants — leftover iron catalyst, carbon and water — could easily skew the results of conductivity tests. Burning those contaminants away, Barron said, creates new possibilities for carbon nanotubes in nanoscale electronics.

The new study appears in the American Chemical Society journal Nano Letters.

The researchers first made multiwalled carbon nanotubes between 40 and 200 nanometers in diameter and up to 30 microns long. They then either heated the nanotubes in a vacuum or bombarded them with argon ions to clean their surfaces.

They tested individual nanotubes the same way one would test any electrical conductor: by touching them with two probes to see how much current passes through the material from one tip to the other. In this case, tungsten probes were attached to a scanning tunneling microscope.

In clean nanotubes, resistance got progressively stronger as the distance increased, as it should. But the results were skewed when the probes encountered surface contaminants, which increased the electric field strength at the tip. And when measurements were taken within 4 microns of each other, regions of depleted conductivity caused by contaminants overlapped, which further scrambled the results.

“We think this is why there’s such inconsistency in the literature,” Barron said. “If nanotubes are to be the next-generation lightweight conductor, then consistent results, batch-to-batch and sample-to-sample, are needed for devices such as motors and generators as well as power systems.”

Heating the nanotubes in a vacuum above 200 degrees Celsius (392 degrees Fahrenheit) reduced surface contamination, but not enough to eliminate inconsistent results, they found. Argon ion bombardment also cleaned the tubes but led to an increase in defects that degrade conductivity.

Ultimately the researchers discovered vacuum annealing nanotubes at 500 degrees Celsius (932 Fahrenheit) reduced contamination enough to measure resistance accurately.

Barron said engineers who use nanotube fibers or films in devices currently modify the material through doping or other means to get the conductive properties they require. But if the source nanotubes are sufficiently decontaminated, they should be able to get the desired conductivity by simply putting their contacts in the right spot.

“A key result of our work is that if contacts on a nanotube are less than 1 micron apart, the electronic properties of the nanotube change from conductor to semiconductor, due to the presence of overlapping depletion zones, which shrink but are still present even in clean nanotubes,” Barron said.

“This has a potential limiting factor on the size of nanotube-based electronic devices,” he said. “Carbon-nanotube devices would be limited in how small they could become, so Moore’s Law would only apply to a point.”

At CES 2018, PixelDisplay will be demonstrating Vivid Color HDR, and implementations for thinner, more portable, brighter, narrow-bezel, cost-effective display products, targeting new HDR standards, with:

  • Increased color gamut and brightness, with better energy efficiency and lower cost, thickness, and weight than previously available
  • Wider-gamut color, for brighter edge-lit HDR LCD’s without the limitations of Quantum Dots, or HDR-crippling narrow-band phosphors
  • Thin MiniLED 2D array direct-backlit for HDR LCD’s, enabling removal of diffuser and light-guide layers, for additional savings
  • Flexible capabilities: “In-die” standard LED applications, “Roll-to-roll” color-conversion layers for MiniLED, and “Wafer-level-patterning” for MicroLED displays
  • Highest compatibility with LCD manufacturing processes, enabling existing LED Backlight designs to meet the new HDR standards
  • Zero heavy metals. Fully RoHS compliant

Following the initial launch of Vivid Color technology May 2017, demonstrated in the Innovation-Zone of SID’s DisplayWeek Conference in LA, showing an industry leading 97.8% of Rec.2020 from a single chip LED, PixelDisplay is directly addressing the HDR market gaps unfilled by Narrow-Band Phosphors, and Quantum Dots.

Mike Trainor, VP of Marketing at PixelDisplay, commented, “We’ve already established our capability for industry-leading laser-like color purity for AR and the next generation 8K standards, but the opportunity we also conveyed in our presentations and SID paper at DisplayWeek was the ability to apply the Vivid Color technology to nearer-term products aiming for prolific HDR compatibility, in thin, portable and narrow-bezel product categories.” Trainor continued, “We’re proud to be showing how near-term this technology is, through side-by-side comparisons with QLED LCD display, and LCD using our entry-level Vivid Color VC65R, the first of the new product series.”

Mike Trainor summarized, “Vivid Color is unique in enabling existing LCD display designs aiming to achieve the UHD Alliance’s MobileHDR and VESA’s new DisplayHDR logo’s requirements, without thickness-adding, bezel-widening. And unlike Narrow-Band KSF Phosphor LED’s, Vivid Color is fully HDR-Compatible, directly supporting inter-frame and dynamic PWM backlight control at high speeds, and very high brightness without disrupting color, sacrificing responsiveness or dynamic range – key challenges of these new HDR standards.”

STMicroelectronics (NYSE:STM) and USound, a fast-growing audio company, have delivered the first silicon micro-speakers resulting from their technology collaboration announced last year. Engineering samples are now with lead customers, and trade demonstrations will take place during CES 2018, in Las Vegas.

These extremely small speakers, expected to be the thinnest in the world and less than half the weight of conventional speakers, enable wearable tech such as earphones, over-the-ear headphones, or Augmented-Reality/Virtual-Reality (AR/VR) headgear to become even more compact and comfortable. Their extremely low power consumption saves extra weight and size by allowing smaller batteries, and unlike conventional speakers they generate negligible heat.

As MEMS (Micro Electro-Mechanical Systems) devices, the speakers are leveraging technology that has already revolutionized the capabilities of smartphones and wearables. High-performing MEMS motion sensors, pressure sensors, and microphones built on silicon chips are the critical enablers for context sensing, navigation, tracking, and other features that mobile users now rely on every day. With MEMS advancements now coming to speakers, designers can further miniaturize the audio subsystem, reduce power consumption, and create innovative features like 3D sound. MEMS-industry analyst Yole Développement values the overall micro-speakers market at $8.7 billion[1] currently, and expects MEMS manufacturers to capture share with silicon-based devices.

“This successful project combines USound’s design flair and ST’s extensive investment in MEMS expertise and processes, including our advanced thin-film piezo technology PeTra (Piezo-electric Transducer),” said Anton Hofmeister, Vice President and GM of MEMS Microactuators Division, STMicroelectronics. “Together, we are winning the race to commercialize MEMS micro-speakers by delivering a more highly miniaturized, efficient, and better-performing solution leveraging the advantages of piezo-actuation.”

“ST has provided the production expertise and manufacturing muscle to realize our original concept as a pace-setting, advanced product ready for consumer-market opportunities,” said Ferruccio Bottoni, CEO of USound. “These tiny speakers are now poised to change the design of audio and hearable products, and open up new opportunities to develop creative audio functionalities.”

In addition to applications in mobiles, audio accessories, and wearables, the new piezo-actuated silicon speakers support innovation in a wide variety of hearable electronics, including home digital assistants, media players, and IoT (Internet-of-Things) devices.

USound will demonstrate prototype AR/VR glasses containing multiple MEMS speakers per side, to invited guests at ST’s private suite during CES 2018. The demo will leverage the speakers’ ultra-thin form factor, low weight, and high sound quality to show how miniaturized audio systems can deliver outstanding experiences, and advanced features such as beam forming for private audio, within the extremely tight size, weight, and power constraints imposed by glasses and other wearables.

Scientists at Tokyo Institute of Technology (Tokyo Tech) and their research team involving researchers of JASRI, Osaka University, Nagoya Institute of Technology, and Nara Institute of Science and Technology have just developed a novel approach to determine and visualize the three-dimensional (3D) structure of individual dopant atoms using SPring-8. The technique will help improve the current understanding of the atomic structures of dopants in semiconductors correlated with their electrical activity and thus help support the development of new manufacturing processes for high-performance devices.

Using a combination of spectro-photoelectron holography, electrical property measurements, and first-principles dynamics simulations, the 3D atomic structures of dopant impurities in a semiconductor crystal were successfully revealed. The need for a better understanding of the atomic structures of dopants in semiconductors had been long felt, mainly because the current limitations on active dopant concentrations result from the deactivation of excess dopant atoms by the formation of various types of clusters and other defect structures.

Soft X-rays excite the core level electrons, leading to the emission of photoelectrons from various atoms, whose waves are then scattered by the surrounding atoms. The interference pattern between the scattered and direct photoelectron waves creates the photoelectron hologram, which may then be captured with an electron analyzer. Credit: Nano Letters

Soft X-rays excite the core level electrons, leading to the emission of photoelectrons from various atoms, whose waves are then scattered by the surrounding atoms. The interference pattern between the scattered and direct photoelectron waves creates the photoelectron hologram, which may then be captured with an electron analyzer. Credit: Nano Letters

The search for techniques to electrically activate the dopant impurities in semiconductors with high efficiency and/or at high concentrations have always been an essential aspect of semiconductor device technology. However, despite various successful developments, the achievable maximum concentration of active dopants remains limited. Given the impact of the dopant atomic structures in this process, these structures had been previously investigated using both theoretical and experimental approaches. However, direct observation of the 3D structures of the dopant atomic arrangements had hitherto been difficult to achieve.

In this study, Kazuo Tsutsui at Tokyo Tech and colleagues involving researchers at JASRI, Osaka University, Nagoya Institute of Technology, and Nara Institute of Science and Technology developed spectro-photoelectron holography using SPring-8, and leveraged the capabilities of photoelectron holography in determining the concentrations of dopants at different sites, based on the peak intensities of the photoelectron spectrum, and classified electrically active / inactive atomic sites. These structures directly related with the density of carriers. In this approach, soft X-ray excitation of the core level electrons leads to the emission of photoelectrons from various atoms, whose waves are then scattered by the surrounding atoms. The resulting interference pattern creates the photoelectron hologram, which may then be captured with an electron analyzer. The photoelectron spectra acquired in this manner contain information from more than one atomic site. Therefore, peak fitting is performed to obtain the photoelectron hologram of individual atomic sites. The combination of this technique with first-principles simulations allows the successful estimation of the 3D structure of the dopant atoms, and the assessment of their different chemical bonding states. The method was used to estimate the 3D structures of arsenic atoms doped onto a silicon surface. The obtained results fully demonstrated the power of the proposed method and allowed confirmation of several previous results.

This work demonstrates the potential of spectro-photoelectron holography for the analysis of impurities in semiconductors. This technique allows analyses that are difficult to perform with conventional approaches and should therefore be useful in the development of improved doping techniques and, ultimately, in supporting the manufacture of high-performance devices.