Tag Archives: letter-pulse-tech

CEA-Leti, a French technology research institute of the CEA and Inac, a joint fundamental research institute between the CEA and the University Grenoble Alpes, today announced a breakthrough towards large-scale fabrication of quantum bits, or qubits, the elementary bricks of future quantum processors. They demonstrated on a 300 mm pre-industrial platform a new level of isotopic purification in a film deposited by chemical vapor deposition (CVD). This enables creating qubits in thin layers of silicon using a very high purity silicon isotope, 28Si, which produces a crystalline quality comparable to thin films usually made of natural silicon.

“Using the isotope 28Si instead of natural silicon is crucial for the optimization of the fidelity of the silicon spin qubit,” said Marc Sanquer, a research director at Inac. “The fidelity of the spin qubit is limited to small values by the presence of nuclear spins in natural silicon. But spin qubit fidelity is greatly enhanced by using 28Si, which has zero nuclear spin. We expect to confirm this with qubits fabricated in a pre-industrial CMOS platform at CEA-Leti.” 

Qubits are the building blocks of quantum information. They can be made in a broad variety of material systems, but when it comes to the crucial issue of large-scale integration, the range of possible choices narrows significantly. Silicon spin qubits have a small size and are compatible with CMOS technology. They therefore present advantages for large-scale integration compared to other types of qubits.

Since 2012, when the first qubits that relied on electron spins were reported, the introduction of isotopically purified 28Si has led to significant enhancement of the spin coherence time. The longer spin coherence lasts, the better the fidelity of the quantum operations.

Quantum effects are essential to understanding how basic silicon micro-components work, but the most interesting quantum effects, such as superposition and entanglement, are not used in circuits. The CEA-Leti and Inac results showed that these effects can be implemented in CMOS transistors operated at low temperature.

CEA-Leti and Inac previously reported preliminary steps for demonstrating a qubit in a process utilizing a natural silicon-on-insulator (SOI) 300 mm CMOS platform1. The qubit is an electrically controlled spin carried by a single hole in a SOI transistor. In a paper published in npj Quantum Information2., CEA-Leti and Inac reported that an electron spin in a SOI transistor can also be manipulated by pure electrical signals, which enable fast and scalable spin qubits.

“To progress towards a practical and useful quantum processor, it is now essential to scale up the qubit,” said Louis Hutin, a research engineer in CEA-Leti’s Silicon Components Division. “This development will have to address variability, reproducibility and electrostatic control quality for elementary quantum bricks, as is done routinely for standard microprocessors.”

To help CEA-Leti and Inac leverage nuclear spin free silicon in the CMOS platform, a silicon precursor was supplied by Air Liquide, using an isotopically purified silane of very high isotopic purity with a 29Si isotope content of less than 0.00250 percent, prepared by the Institute of Chemistry of High-Purity Substances at the Russian Academy of Sciences. The 29Si isotope is present at 4.67 percent in natural silicon and is the only stable isotope of silicon that carries a nuclear spin limiting the qubit coherence time.

A secondary ion mass spectrometry (SIMS) analysis done on the CVD-grown layer using this purified silane precursor showed29Si concentration less than 0.006 percent, and 30Si less than 0.002 percent, while 28Si concentration was more than 99.992 percent. These unprecedented levels of isotopic purification for a CVD-grown epilayer on 300 mm substrates are associated with surfaces that are smooth at the atomic scale, as verified by atomic force microscopy (AFM), haze and X-ray reflectometry measurements.

Leveraging their scientific and technological expertise, and the specific opportunities associated with the 300 mm silicon platform on the Minatec campus, CEA-Leti and Inac will continue to contribute to the scientific, technological and industrial dynamic on quantum technologies, enhanced by the implementation of the EC’s FET Flagships initiative in this domain.

  1. “A CMOS silicon spin qubit”, arXiv:1605.07599 Nature Communications 7, Article number: 13575 (2016) doi:10.1038/ncomms13575
  1. “Electrically driven electron spin resonance mediated by spin-valley-orbit coupling in a silicon quantum dot”, Nature PJ Quantum Information (2018) 4:6; doi:10.1038/s41534-018-0059-1

GLOBALFOUNDRIES today announced a new ecosystem partner program, called RFWave, designed to simplify RF design and help customers reduce time-to-market for a new era of wireless devices and networks.

The last few years there has been an increasing demand for connected devices and systems that will require innovations in radio technologies to support the new modes of operation and higher capabilities. The RFWave Partner Program builds upon GF’s 5G vision and roadmap, with a focus on the company’s industry-leading radio frequency (RF) solutions, such as FD-SOI, RF CMOS (bulk and advanced CMOS nodes), RF SOI and silicon germanium (SiGe) technologies. The program provides a low-risk, cost-effective path for designers seeking to build highly optimized RF solutions for a range of wireless applications such as IoT across various wireless connectivity and cellular standards, standalone or transceiver integrated 5G front end modules, mmWave backhaul, automotive radar, small cell and fixed wireless and satellite broadband.

RFWave enables customers to build innovative RF solutions as well as packaging and test solutions. Initial partners have committed a set of key offerings to the program, including:

  • tools (EDA) that complement industry leading design flows by adding specific modules to easily leverage features of GF’s RF technology platforms,
  • a comprehensive library of design elements (IP), including foundation IP, interfaces and complex IP to enable foundry customers to start their designs using pre-validated IP elements,
  • resources (design consultation, services), trained and globally distributed, for Partners to gain easy access to support in developing solutions using GF’s RF technologies

“An explosion of digital information is expected to drive an enormous amount of growth in the coming years and our customers are already preparing for a future of seamless, reliable ultra high data rate wireless connectivity everywhere,” said Bami Bastani, senior vice president of GF’S RF Business Unit. “As a leader in RF, GF’s RFWave program takes industry collaboration to a new level, enabling our customers to build differentiated, highly integrated RF-tailored solutions that are designed to accelerate the next wave of technology.”

The RFWave Partner Program creates an open framework to allow selected partners to integrate their products or services into a validated, plug-and-play catalog of design solutions. This level of integration allows customers to create high-performance designs while minimizing development costs through access to a broad set of quality offerings, specific to RF technology. The partner ecosystem positions members and customers to take advantage of ubiquitous connectivity and the broad adoption of GF’s industry-leading RF technology platforms.

Initial members of the RFWave Partner Program are: asicNorth, Cadence, CoreHW, CWS, Keysight Technologies, Spectral Design, and WEASIC. These companies have already initiated work to deliver innovative, highly optimized RF solutions.

An unexpected phenomenon known as zero field switching (ZFS) could lead to smaller, lower-power memory and computing devices than presently possible. The image shows a layering of platinum (Pt), tungsten (W), and a cobalt-iron-boron magnet (CoFeB) sandwiched at the ends by gold (Au) electrodes on a silicon (Si) surface. The gray arrows depict the overall direction of electric current injected into the structure at the back of the gold (Au) contact and coming out the front gold contact pad.

This is an illustration of an unexpected phenomenon known as zero field switching (ZFS) that could lead to smaller, lower-power memory and computing devices than presently possible. The image shows a layering of platinum (Pt), tungsten (W), and a cobalt-iron-boron magnet (CoFeB) sandwiched at the ends by gold (Au) electrodes on a silicon (Si) surface. The gray arrows depict the overall direction of electric current injected into the structure at the back of the gold (Au) contact and coming out the front gold contact pad. The CoFeB layer is a nanometer-thick magnet that stores a bit of data. A "1" corresponds to the CoFeB magnetization pointing up (up arrow), and a "0" represents the magnetization pointing down (down arrow). Credit: Gopman/NIST

This is an illustration of an unexpected phenomenon known as zero field switching (ZFS) that could lead to smaller, lower-power memory and computing devices than presently possible. The image shows a layering of platinum (Pt), tungsten (W), and a cobalt-iron-boron magnet (CoFeB) sandwiched at the ends by gold (Au) electrodes on a silicon (Si) surface. The gray arrows depict the overall direction of electric current injected into the structure at the back of the gold (Au) contact and coming out the front gold contact pad. The CoFeB layer is a nanometer-thick magnet that stores a bit of data. A “1” corresponds to the CoFeB magnetization pointing up (up arrow), and a “0” represents the magnetization pointing down (down arrow). Credit: Gopman/NIST

The CoFeB layer is a nanometer-thick magnet that stores a bit of data. A “1” corresponds to the CoFeB magnetization pointing up (up arrow), and a “0” represents the magnetization pointing down (down arrow). The “0” or “1” can be read both electrically and optically, as the magnetization changes the reflectivity of light shining on the material through another phenomenon known as the magneto-optical Kerr effect (MOKE).

In the device, electric current can flip the data state between 0 and 1. Previous devices of this type have also required a magnetic field or other more complex measures to change the material’s magnetization. Those earlier devices are not very useful for building stable, non-volatile memory devices.

A breakthrough occurred in a research collaboration between The Johns Hopkins University and NIST. The team discovered that they could flip the CoFeB magnetization in a stable fashion between the 0 and 1 states by sending only electric current through the Pt and W metal layers adjacent to the CoFeB nanomagnet. They did not need a magnetic field. This ZFS (zero-field switching) effect was a surprise and had not been theoretically predicted.

In their work, the researchers created a special kind of electric current known as a “spin” current. The electrons that carry electric current possess a property known as spin which can be imagined as a bar magnet pointing in a specific direction through the electron. Increasingly exploited in the emerging field known as “spintronics,” spin current is simply electric current in which the spins of the electrons are pointing in the same direction. As an electron moves through the material, the interaction between its spin and its motion (called a spin-orbit torque, SOT) creates a spin current where electrons with one spin state move perpendicular to the current in one direction and electrons with the opposite spin state move in the opposite direction. The resulting spins that have moved adjacent to the CoFeB magnetic layer exert a torque on that layer, causing its magnetization to be flipped. Without the spin current the CoFeB magnetization is stable against any fluctuations in current and temperature. This unexpected ZFS effect poses new questions to theorists about the underlying mechanism of the observed SOT-induced switching phenomenon.

Details of the spin-orbit torque are illustrated in the diagram. The purple arrows show the spins of the electrons in each layer. The blue curved arrow shows the direction in which spins of that type are being diverted. (For example, in the W layer, electrons with spin to the left in the x-y plane are diverted to move upward toward the CoFeB and the electron spins to the right are diverted to move down toward the Pt.) Note the electron spins in the Pt with spin to the right (in the x-y plane), however, are diverted to move upward toward the W and the electron spins with spin to the left are diverted to move downward toward the Si. This is opposite to the direction the electron spins in the W are moving, and this is due to differences in the SOT experienced by electrons moving through Pt and those moving through W. In fact, it is this difference in the way the electrons move through each of these two conductors that may be important to enabling the unusual ZFS effect.

The research team, including NIST scientists Daniel Gopman, Robert Shull, and NIST guest researcher Yury Kabanov, and The Johns Hopkins University researchers Qinli Ma, Yufan Li and Professor Chia-Ling Chien, report their findings today in Physical Review Letters.

Ongoing investigations by the researchers seek to identify other prospective materials that enable zero-field-switching of a single perpendicular nanomagnet, as well as determining how the ZFS behavior changes for nanomagnets possessing smaller lateral sizes and developing the theoretical foundation for this unexpected switching phenomenon.

Some novel materials that sound too good to be true turn out to be true and good. An emergent class of semiconductors, which could affordably light up our future with nuanced colors emanating from lasers, lamps, and even window glass, could be the latest example.

These materials are very radiant, easy to process from solution, and energy-efficient. The nagging question of whether hybrid organic-inorganic perovskites (HOIPs) could really work just received a very affirmative answer in a new international study led by physical chemists at the Georgia Institute of Technology.

Laser light in the visible range is processed for use in the testing of quantum properties in materials in Carlos Silva's lab at Georgia Tech. Credit: Georgia Tech/Allison Carter

Laser light in the visible range is processed for use in the testing of quantum properties in materials in Carlos Silva’s lab at Georgia Tech. Credit: Georgia Tech/Allison Carter

The researchers observed in an HOIP a “richness” of semiconducting physics created by what could be described as electrons dancing on chemical underpinnings that wobble like a funhouse floor in an earthquake. That bucks conventional wisdom because established semiconductors rely upon rigidly stable chemical foundations, that is to say, quieter molecular frameworks, to produce the desired quantum properties.

“We don’t know yet how it works to have these stable quantum properties in this intense molecular motion,” said first author Felix Thouin, a graduate research assistant at Georgia Tech. “It defies physics models we have to try to explain it. It’s like we need some new physics.”

Quantum properties surprise

Their gyrating jumbles have made HOIPs challenging to examine, but the team of researchers from a total of five research institutes in four countries succeeded in measuring a prototypical HOIP and found its quantum properties on par with those of established, molecularly rigid semiconductors, many of which are graphene-based.

“The properties were at least as good as in those materials and may be even better,” said Carlos Silva, a professor in Georgia Tech’s School of Chemistry and Biochemistry. Not all semiconductors also absorb and emit light well, but HOIPs do, making them optoelectronic and thus potentially useful in lasers, LEDs, other lighting applications, and also in photovoltaics.

The lack of molecular-level rigidity in HOIPs also plays into them being more flexibly produced and applied.

Silva co-led the study with physicist Ajay Ram Srimath Kandada. Their team published the results of their study on two-dimensional HOIPs on March 8, 2018, in the journal Physical Review Materials. Their research was funded by EU Horizon 2020, the Natural Sciences and Engineering Research Council of Canada, the Fond Québécois pour la Recherche, the Research Council of Canada, and the National Research Foundation of Singapore.

The ‘solution solution’

Commonly, semiconducting properties arise from static crystalline lattices of neatly interconnected atoms. In silicon, for example, which is used in most commercial solar cells, they are interconnected silicon atoms. The same principle applies to graphene-like semiconductors.

“These lattices are structurally not very complex,” Silva said. “They’re only one atom thin, and they have strict two-dimensional properties, so they’re much more rigid.”

“You forcefully limit these systems to two dimensions,” said Srimath Kandada, who is a Marie Curie International Fellow at Georgia Tech and the Italian Institute of Technology. “The atoms are arranged in infinitely expansive, flat sheets, and then these very interesting and desirable optoelectronic properties emerge.”

These proven materials impress. So, why pursue HOIPs, except to explore their baffling physics? Because they may be more practical in important ways.

“One of the compelling advantages is that they’re all made using low-temperature processing from solutions,” Silva said. “It takes much less energy to make them.”

By contrast, graphene-based materials are produced at high temperatures in small amounts that can be tedious to work with. “With this stuff (HOIPs), you can make big batches in solution and coat a whole window with it if you want to,” Silva said.

Funhouse in an earthquake

For all an HOIP’s wobbling, it’s also a very ordered lattice with its own kind of rigidity, though less limiting than in the customary two-dimensional materials.

“It’s not just a single layer,” Srimath Kandada said. “There is a very specific perovskite-like geometry.” Perovskite refers to the shape of an HOIPs crystal lattice, which is a layered scaffolding.

“The lattice self-assembles,” Srimath Kandada said, “and it does so in a three-dimensional stack made of layers of two-dimensional sheets. But HOIPs still preserve those desirable 2D quantum properties.”

Those sheets are held together by interspersed layers of another molecular structure that is a bit like a sheet of rubber bands. That makes the scaffolding wiggle like a funhouse floor.

“At room temperature, the molecules wiggle all over the place. That disrupts the lattice, which is where the electrons live. It’s really intense,” Silva said. “But surprisingly, the quantum properties are still really stable.”

Having quantum properties work at room temperature without requiring ultra-cooling is important for practical use as a semiconductor.

Going back to what HOIP stands for — hybrid organic-inorganic perovskites – this is how the experimental material fit into the HOIP chemical class: It was a hybrid of inorganic layers of a lead iodide (the rigid part) separated by organic layers (the rubber band-like parts) of phenylethylammonium (chemical formula (PEA)2PbI4).

The lead in this prototypical material could be swapped out for a metal safer for humans to handle before the development of an applicable material.

Electron choreography

HOIPs are great semiconductors because their electrons do an acrobatic square dance.

Usually, electrons live in an orbit around the nucleus of an atom or are shared by atoms in a chemical bond. But HOIP chemical lattices, like all semiconductors, are configured to share electrons more broadly.

Energy levels in a system can free the electrons to run around and participate in things like the flow of electricity and heat. The orbits, which are then empty, are called electron holes, and they want the electrons back.

“The hole is thought of as a positive charge, and of course, the electron has a negative charge,” Silva said. “So, hole and electron attract each other.”

The electrons and holes race around each other like dance partners pairing up to what physicists call an “exciton.” Excitons act and look a lot like particles themselves, though they’re not really particles.

Hopping biexciton light

In semiconductors, millions of excitons are correlated, or choreographed, with each other, which makes for desirable properties, when an energy source like electricity or laser light is applied. Additionally, excitons can pair up to form biexcitons, boosting the semiconductor’s energetic properties.

“In this material, we found that the biexciton binding energies were high,” Silva said. “That’s why we want to put this into lasers because the energy you input ends up to 80 or 90 percent as biexcitons.”

Biexcitons bump up energetically to absorb input energy. Then they contract energetically and pump out light. That would work not only in lasers but also in LEDs or other surfaces using the optoelectronic material.

“You can adjust the chemistry (of HOIPs) to control the width between biexciton states, and that controls the wavelength of the light given off,” Silva said. “And the adjustment can be very fine to give you any wavelength of light.”

That translates into any color of light the heart desires.

A research team from Tokyo Institute of Technology (Tokyo Tech) and Waseda University have successfully produced high-quality thin film monocrystalline silicon with a reduced crystal defect density down to the silicon wafer level at a growth rate that is more than 10 times higher than before. In principle, this method can improve the raw material yield to nearly 100%. Therefore, it can be expected that this technology will make it possible to drastically reduce manufacturing costs while maintaining the power generation efficiency of monocrystalline silicon solar cells, which are used in most high efficient solar cells.

This is the monocrystalline Si thin film peeled off using adhesive tape. Credit: CrystEngComm

This is the monocrystalline Si thin film peeled off using adhesive tape. Credit: CrystEngComm

Background

Solar power generation is a method of generating power where solar light energy is converted directly into electricity using a device called a “solar cell.” Efficiently converting the solar energy that is constantly striking the earth to generate electricity is an effective solution to the problem of global warming related to CO2emissions. By making the monocrystalline Si solar cells that are at the core of solar power generation systems thinner, it is possible to greatly reduce raw material costs, which account for about 40% of the current module, and by making them flexible and lighter, usage can be expected to expand and installation costs can be expected to decrease.

In addition, as a method of reducing manufacturing cost, thin-film monocrystalline Si solar cells that use porous silicon (Double Porous Silicon Layer: DPSL) via lift-off are attracting attention as having a competitive edge in the future.

Among the technical challenges related to monocrystalline Si solar cells using lift-off are 1) the formation of a high-quality thin film Si at the Si wafer level, 2) achieving a porous structure that can easily be lifted off (peeled off), 3) improving the growth rate and Si raw material yield (necessary equipment costs are determined by the growth rate), and 4) being able to use the substrate after lift-off without any waste.

In order to overcome challenge 1), it was necessary to clarify the main factors that determine the quality of thin film crystals grown on porous silicon, and to develop a technique for controlling these.

Overview of research achievement

A joint research team consisting of Professor Manabu Ihara and Assistant Professor Kei Hasegawa of the Tokyo Tech, and Professor Suguru Noda of Waseda University has developed a high-quality thin film monocrystalline silicon with a thickness of about 10 μm and a reduced crystal defect density down to the silicon wafer level at a growth rate that is more than 10 times higher than before. First, double-layer nano-order porous silicon is generated on the surface of a monocrystalline wafer using an electrochemical technique. Next, the surface was smoothed to a roughness of 0.2 to 0.3 nm via a unique zone heating recrystallization method (ZHR method), and this substrate was used for high-speed growth to obtain a moonocrystalline thin film with high crystal quality. The grown film can easily be peeled off using the double-layer porous Si layer, and the substrate can be reused or used as an evaporation source for thin film growth, which greatly reduces material loss. When the surface roughness of the underlying substrate is reduced by changing the ZHR method conditions, the defect density of the thin film crystal that was grown decreased, and the team eventually succeeded in reducing it to the Si wafer level of about 1/10th. This quantitatively shows that a surface roughness in the range of only 0.1-0.2 nm (level of atoms to several tens of layers) has an important impact on the formation of crystal defects, which is also of interest as a crystal growth mechanism.

The film formation rate and the conversion rate of the Si source to the thin film Si are bottlenecks in the production of thin-film monocrystalline Si. With chemical vapor deposition (CVD), which is mainly used for epitaxy, the maximum film forming rate is a few μm/h and the yield is about 10%. At the Noda Laboratory of Waseda University, instead of the regular physical vapor deposition (PVD) where raw Si is vaporized at around its melting point of 1414 ?C, by vaporizing the raw Si at much higher temperature of >2000 ?C, a rapid evaporation method (RVD) was developed with a high Si vapor pressure capable of depositing Si at 10 μm/min.

It was found that the ZHR technology developed this time can resolves technical problems and drastically reduce the manufacturing cost of the lift-off process.

Future development

Based on the results of this study, not only did the team discover the main factors for improving the quality of crystals during rapid growth on porous silicon used for the lift-off process, they succeeded in controlling these. In the future, measurement of the carrier lifetime of the thin film, which is directly connected to the performances of solar cells, and fabrication of solar cells will be carried out with the goal of putting the technology into practical use. The use of this Si thin films as low cost bottom cells in tandem type solar cells with an efficiency of over 30% will also be considered.

The results are published in the Royal Society of Chemistry (RSC) journal CrystEngComm and will be featured on the inside front cover of the issue.

Scientists of Karlsruhe Institute of Technology (KIT) have succeeded in monitoring the growth of minute gallium arsenide wires. Their findings do not only provide for a better understanding of growth, they also enable approaches to customizing nanowires with special properties for certain applications in the future. Gallium arsenide is a semiconductor material widely used in infrared remote controls, high-frequency technology for mobile phones, conversion of electric signals into light in glass-fiber cables, and solar cells for space technology. The results were presented in the journal Nano Letters by the team of Philipp Schroth of KIT and the University of Siegen.

For wire production, the scientists used the self-catalyzed vapor-liquid-solid process (VLS process). Minute liquid gallium droplets are deposited on a hot silicon crystal of around 600°C in temperature. Then, this wafer is subjected to directed beams of gallium atoms and arsenic molecules that dissolve in the gallium droplets. After some time, nanowires start to grow below the droplets that act as catalysts for the longitudinal growth of the wires. “This process is quite well established, but it has been impossible so far to specifically control it. To achieve this, the details of growth have to be understood first,” co-author Ludwig Feigl of KIT says.

For the studies, the team used a portable chamber specifically designed by KIT’s Institute for Photon Science and Synchrotron Radiation (IPS) with funds of the Federal Ministry of Education and Research (BMBF). The researchers installed the chamber in the research light source PETRA III of the German Electron Synchrotron (DESY) and took X-ray pictures every minute to determine the structure and diameter of the growing nanowires. Finally, they measured the fully grown nanowires with an electron microscope. “We found that growth of nanowires is not only caused by the VLS process, but also by a second component that was observed and quantified directly for the first time in this experiment. This so-called side-wall growth makes the wires gain width,” says Philipp Schroth. In the course of the growth process, the gallium droplets become larger due to constant gallium vapor deposition. This has a far-reaching impact. “As the droplet size changes, the contact angle between the droplet and the surface of the wires changes as well. In certain cases, this causes the wire to suddenly continue growing with another crystal structure,” Feigl says. This change is of relevance to applications, as the structure and shape of the nanowires considerably affect the properties of the resulting material.

One of the problems for Javier Vela and the chemists in his Iowa State University research group was that a toxic material worked so well in solar cells.

And so any substitute for the lead-containing perovskites used in some solar cells would have to really perform. But what could they find to replace the perovskite semiconductors that have been so promising and so efficient at converting sunlight into electricity?

What materials could produce semiconductors that worked just as well, but were safe and abundant and inexpensive to manufacture?

“Semiconductors are everywhere, right?” Vela said. “They’re in our computers and our cell phones. They’re usually in high-end, high-value products. While semiconductors may not contain rare materials, many are toxic or very expensive.”

Vela, an Iowa State associate professor of chemistry and an associate of the U.S. Department of Energy’s Ames Laboratory, directs a lab that specializes in developing new, nanostructured materials. While thinking about the problem of lead in solar cells, he found a conference presentation by Massachusetts Institute of Technology researchers that suggested possible substitutes for perovskites in semiconductors.

Vela and Iowa State graduate students Bryan Rosales and Miles White decided to focus on sodium-based alternatives and started an 18-month search for a new kind of semiconductor. The work was supported by Vela’s five-year, $786,017 CAREER grant from the National Science Foundation. CAREER grants are the foundation’s most prestigious awards for early career faculty.

They came up with a compound that features sodium, which is cheap and abundant; bismuth, which is relatively scarce but is overproduced during the mining of other metals and is cheap; and sulfur, the fifth most common element on Earth. The researchers report their discovery in a paper recently published online by the Journal of the American Chemical Society.

The paper’s subtitle is a good summary of their work: “Toward Earth-Abundant, Biocompatible Semiconductors.”

“Our synthesis unlocks a new class of low-cost and environmentally friendly ternary (three-part) semiconductors that show properties of interest for applications in energy conversion,” the chemists wrote in their paper.

In fact, Rosales is working to create solar cells that use the new semiconducting material.

Vela said variations in synthesis – changing reaction temperature and time, choice of metal ion precursors, adding certain ligands – allows the chemists to control the material’s structure and the size of its nanocrystals. And that allows researchers to change and fine tune the material’s properties.

Several of the material’s properties are already ideal for solar cells: The material’s band gap – the amount of energy required for a light particle to knock an electron loose – is ideal for solar cells. The material, unlike other materials used in solar cells, is also stable when exposed to air and water.

So, the chemists think they have a material that will work well in solar cells, but without the toxicity, scarcity or costs.

“We believe the experimental and computational results reported here,” they wrote in their paper, “will help advance the fundamental study and exploration of these and similar materials for energy conversion devices.”

Imec, a research and innovation hub in nanoelectronics and digital technologies, today presented its annual Lifetime of Innovation Award to Dr. Irwin Jacobs, Founding Chairman and CEO Emeritus of Qualcomm. The annual industry honor is presented to the individual who has significantly advanced the field of semiconductor technology.  The formal presentation will be made at the global Imec Technology Forum (ITF) in May in Belgium.

In making the announcement, Luc Van den hove, president and CEO of imec, said: “Irwin Jacobs’ many technological contributions laid the groundwork for creating the mobile industry and markets that we know today. Under his leadership, Qualcomm developed two-way mobile satellite communications and tracking systems deemed the most advanced in the world. He pioneered spread-spectrum technology and systems using CDMA (code division multiple access), which became a digital standard for cellular phone communications. Together, these technologies opened mobile communications to the global consumer market.”

Irwin Jacobs began his career first as an assistant and then associate professor of electrical engineering at MIT and, later, as professor of computer science and engineering at the University of California in San Diego. While at MIT, he co-authored Principles of Communication Engineering, a textbook still in use. He began his corporate life as a cofounder of Linkabit, which developed satellite encryption devices.  In 1985, he co-founded Qualcomm, serving as CEO until 2005 and chairman through 2009.  His numerous awards include the National Medal of Technology, the Marconi Prize, and the Carnegie Medal of Philanthropy.  His honors include nine honorary degrees including doctor of engineering from the National Tsing Hua University, Taiwan.

Imec initiated the Lifetime of Innovation Award in 2015 at their annual global forum known as ITF (Imec Technology Forum).  The award marks milestones that have transformed the semiconductor industry.  The first recipient was Dr. Morris Chang, whose foundry model launched the fabless semiconductor industry, spurring creation of new innovative companies.  In 2016, Gordon Moore was honored, creator of the famous Moore’s law theory and co-founder of Intel.  Dr. Kinam Kim was honored in 2017 for his contributions in memory technologies and his visionary leadership at Samsung.

Luc Van den hove concluded, saying: “Our mission is to create innovation through collaboration. By gathering global technology leaders at the ITF, imec provides an open forum to share issues and trends challenging the semiconductor industry. In this international exchange, imec and participants outline ways to collaborate in bringing innovative solutions to market.”

Thermo Fisher Scientific, the world leader in serving science, announces new products that improve quality control and yield in semiconductor manufacturing. These new products will be showcased at SEMICON China (Hall N5 #5619), Shanghai, March 14-16, 2018.

“Thermo Fisher has deep roots in the advanced analytical technologies used to control manufacturing processes and diagnose the root causes of process and product failures in semiconductor and display manufacturing,” said Rob Krueger, vice president and general manager, semiconductor, Thermo Fisher. “This week, we are introducing new products that help propel the rapid pace of innovation and continuing expansion of semiconductor manufacturing capacity in Asia, and particularly, in China.”

Verios G4 Extreme High-Resolution SEM

The Thermo Scientific Verios G4 extreme high-resolution (XHR) scanning electron microscope (SEM) delivers the capability and flexibility needed to determine root cause defects, yield losses, and process and product failures.

“The Verios G4 is an SEM-only solution derived from our widely successful Helios family of DualBeam (focused ion beam/SEM) instruments,” said Krueger. “It offers industry leading performance across a wide range of conditions, especially at the low voltages required for beam-sensitive materials used in advanced processes.”

Hyperion II Fast & Efficient Nanoprober

Nanoprobers make direct electrical measurements of individual transistors. The new Thermo Scientific Hyperion II, the only commercially available nanoprober based on an atomic force microscope (AFM), eliminates the vacuum requirements and e-beam/sample interactions of SEM-based nanoprobers. The Hyperion II’s automated operation and imaging modes are designed for speed and ease of use. In addition, its ability to precisely localize electrical faults may improve the speed and efficiency of subsequent DualBeam or TEM analysis.

iCAP TQs ICP-MS for Fast and Reliable Chemical Monitoring

The Thermo Scientific iCAP TQs inductively coupled plasma-mass spectrometer (ICP-MS) is a dedicated semiconductor version of the well-established iCAP TQ ICP-MS. It provides the fast, reliable and reproducible measurement of low-level contaminants in ultra-high purity (UHP) chemicals required to support automated at-line monitoring and statistical process control for advanced semiconductor manufacturing processes. The iCAP TQs ICP-MS provides new levels of ultra-low detection and simplicity in a single high-performance solution. Moving chemical analysis from the lab to the fab is now possible with this new system and allows at-line control of chemical baths, which optimizes response times.

The Silicon Integration Initiative’s (Si2) Compact Model Coalition (CMC) has approved two integrated circuit design simulation standards that target the fast-growing global market for gallium nitride semiconductors.

The approved standards are the 12th and 13th models currently funded and supported by the CMC, a collaborative group that develops and maintains cost-saving SPICE (Simulation Program with Integrated Circuit Emphasis) models for IC design.

John Ellis, president and CEO, said gallium nitride devices are used in many high-power and high-frequency applications, including satellite communications, radar, cellular, broadband wireless systems, and automotive. “Although it’s currently a small market, gallium nitride devices are expected to show remarkable growth over the coming years.”

To reduce research and developments costs and increase simulation accuracy, the semiconductor industry relies on the CMC to share resources for funding standard SPICE models. Si2 is a research and development joint venture focused on IC design and tool operability standards. “Once the standard models are proven and accepted by CMC, they are incorporated into design tools widely used by the semiconductor industry. The equations at work in the standard model-setting process are developed, refined and maintained by leading universities and national laboratories. The CMC directs and funds the universities to standardize and improve the models,” Ellis explained.

Dr. Ana Villamor, technology and market analyst at Yole Développement (Yole), Lyon, France, said that “2015 and 2016 were exciting years for the gallium nitride power business. We project an explosion of this market with 79% CAGR between 2017 and 2022. Market value will reach US $460 million at the end of the period1. It’s still a small market compared to the impressive US $30 billion silicon power semiconductor market,” Villamor said. “However, its expected growth in the short term is showing the enormous potential of the power gallium nitride technology based on its suitability for high performance and high frequency solutions.”

Yole_GaN_power_device_market_size_split_by_application_M_

Peter Lee, manager at Micron Memory Japan and CMC chair, said that “Gallium nitride devices are playing an increasingly important part in the field of RF and power electronics. With these two advanced models established as the first, worldwide gallium nitride model standards, efficiencies in design will greatly increase by making it possible to take into account accurate device physical behavior in design, and enabling the use of the various simulation tools in the industry with consistent results.”

Click here to download standard models.