Category Archives: Process Materials

Research managed by SUNY Polytechnic Institute (SUNY Poly) and conducted by a number of collaborating institutions has led to findings that have been named a top ten 2016 breakthrough in physics by Physics World. The publication recently named the SUNY Poly-led Institute for Nanoelectronics Discovery and Exploration’s (INDEX) “Theme I” work on the negative refraction of electrons in graphene p-n junctions as “a top ten breakthrough,” as it supports the physics for p-n junctions in graphene, which could lead to more powerful and energy efficient computing capabilities in the future.

“SUNY Poly’s position as a world class research institution is unmatched, and our faculty and students should be proud to be a part of that success,” said Dr. Bahgat Sammakia, Interim President of SUNY Polytechnic Institute. “It’s an incredible honor to have research managed by the talented people here at SUNY Poly recognized among the top ten physics breakthroughs of this past year, and I salute the SUNY Poly INDEX team and the researchers at partnering institutions who, collectively, enabled this fascinating research.”

As part of the research, scientists created a p-n junction, a building block of many modern day semiconductor-based electronic devices, in graphene, a two-dimensional honeycomb-shaped form of carbon that is incredibly strong and conductive. By ensuring that the p-n junction interface was smooth, the researchers minimized reflections, which enabled them to measure the negative refraction of electrons, an accomplishment that could one day form the basis of a new type of electronic switch, potentially replacing the transistor, which is currently the basis of computers worldwide. While this research shows that this new type of switch is possible, it could still take many years for any practical applications to result.

“We are excited that this great work of physics has been recognized by Physics World, and as part of the SUNY Poly team, we are thrilled to have solidified INDEX’s funding and look forward to continuing this important work, ” said SUNY Poly Vice President for Research Dr. Michael Liehr. “This acknowledgement is a testament not only to SUNY Poly’s ability to lead collaborations that can have significant research impact, but also to working collaboratively as research partners with other leading institutions such as Columbia University.”

The research that led to the notable findings was specifically conducted at Columbia University, the University of Virginia, and Harvard University, and was managed by SUNY Poly; Cornell University, the National Institute for Materials Science in Japan, and IBM were also recognized by Physics World for their teams’ contributions.

“This work is significant for proving the fundamental physics of the graphene p-n junction, and we are excited that the research of ‘Theme I’ of INDEX has resulted in this recognition,” SUNY Poly Interim Dean of the College of Nanoscale Science and Empire Innovation Professor of Nanoscale Science Dr. Alain Diebold said. “This is a credit to researchers Cory Dean and Jim Hone of Columbia University, who fabricated and measured the test structures using a method called magnetic steering, as well as Avik Ghosh of the University of Virginia, who modeled and simulated the data enabling the interpretation and helping to design new test structures. SUNY Poly was proud to play an enabling role.”

The research was conducted under the SUNY Poly-led umbrella of INDEX, which is one of three active centers in the Semiconductor Research Corporation’s Nanoelectronics Initiative leveraging faculty and students across ten universities. INDEX has three research areas, or themes: graphene p-n junction devices, spintronic devices, and fabrication – with a goal to develop a new switch to replace the transistor. Currently, Dr. Alain Diebold serves as INDEX’s Director, following the tenure of Dr. Michael Liehr, who had previously served as director at the Nanoelectronics Research Institute-funded center. In addition, INDEX is a Semiconductor Research Corporation (SRC) program sponsored by the Nano-Electronics Research Corporation (NERC) and the National Institute of Standards and Technology (NIST).

Based on a study of the optical properties of novel ultrathin semiconductors, researchers of Ludwig-Maximilians-Universitaet (LMU) in Munich have developed a method for rapid and efficient characterization of these materials.

Chemical compounds based on elements that belong to the so-called transition metals can be processed to yield atomically thin two-dimensional crystals consisting of a monolayer of the composite in question. The resulting materials are semiconductors with surprising optical properties. In cooperation with American colleagues, a team of LMU physicists led by Alexander Högele has now explored the properties of thin-film semiconductors made up of transition metal dichalcogenides (TMDs). The researchers report their findings in the journal Nature Nanotechnology.

These semiconductors exhibit remarkably strong interaction with light and therefore have great potential for applications in the field of opto-electronics. In particular, the electrons in these materials can be excited with polarized light. “Circularly polarized light generates charge carriers that exhibit either left- or right-handed circular motion. The associated angular momentum is quantized and described by the so-called valley index which can be detected as valley polarization,” Högele explains. In accord with the laws of quantum mechanics, the valley index can be used just like quantum mechanical spin to encode information for many applications including quantum computing.

However, recent studies of the valley index in TMD semiconductors have led to controversial results. Different groups worldwide have reported inconsistent values for the degree of valley polarization. With the aid of their newly developed polarimetric method and using monolayers of the semiconducting TMD molybdenum disulfide as a model system, the LMU researchers have now clarified the reasons for these discrepancies: “Response to polarized light turns out to be very sensitive to the quality of the crystals, and can thus vary significantly within the same crystal,” Högele says. “The interplay between crystal quality and valley polarization will allow us to measure rapidly and efficiently those properties of the sample that are relevant for applications based on the valley quantum degree of freedom.”

Moreover, the new method can be applied to other monolayer semiconductors and systems made up of several different materials. In the future, this will enable the functionalities of devices based on atomically thin semiconductors — such as novel types of LEDs — to be characterized swiftly and economically.

The global gallium arsenide (GaAs) components market is expected to grow at a CAGR of over 4% during the forecast period, according to Technavio’s latest report.

In this report, Technavio covers the market outlook and growth prospects of the global GaAs components market for 2017-2021. By end-users, this market is divided into mobile devices and wireless communications segments.

The global GaAs components market is expected to grow to USD 9.13 billion by 2021, with over 54% of the revenue being generated from the mobile devices segment. The quickly developing 3G and 4G networks are enabling the quick growth of the market segment.

The rising adoption of smartphones and tablets is acting as a major driving factor for this market, with number of smartphone shipments expected to hit 2 billion by 2020. This growth in number of shipments will drive the demand for GaAs components used in mobile handsets, particularly GaAs power amplifiers.

Technavio’s research study segments the global GaAs components market into the following regions:

  • APAC
  • Americas
  • EMEA

APAC: largest GaAs component market segment

“APAC is the global leader in the market, accounting for almost 78% of the total market revenue in 2016. The market dominance is primarily because of the high demand for GaAs components from communication device manufacturers in the region. Also, increasing demand for power applications, along with high-growth economies, is a major driver of the GaAs components market in the region,” says Sunil Kumar Singh, one of the lead analysts at Technavio for embedded systems research.

The increasing smartphone penetration in developing countries and rapidly developing wireless infrastructure are driving the high adoption of GaAs components in the region. Companies such as Samsung, LG, HTC, and Sony are investing heavily to launch better smartphones, which is compatible with 3G/4G technologies. These new-generation mobile phones integrate three to four times more power amplifiers when compared to previous generation smartphones, which means increased demand for GaAs components.

Technavio’s sample reports are free of charge and contain multiple sections of the report including the market size and forecast, drivers, challenges, trends, and more.

Americas: expansion of 4G networks driving GaAs components market the region

Analysts at Technavio forecast the Americas to showcase a CAGR of 4.31% during the forecast period, of which most of the growth will be driven by the expansion of 4G networks in the region. North America is witnessing rapid expansion of its 4G network to make an easier transition to the upcoming 5G network. Apple and Skyworks Solutions are among the biggest consumers of GaAs components for their application in mobile power amplifiers.

GaAs components also find wide application in radar and defense systems. Currently, the US Department of Defense(DoD) is investing significantly in GaAs components to improve the efficiency of its current radar applications. Additionally, GaAs components are expected to attract demand from the military sector, thereby boosting the revenue contribution from the region.

EMEA: high demand from the automotive industry

“The GaAs components saw maximum adoption from the thriving automotive industry in the region. The region will also invest in the adoption of LEDs for the general lighting and automotive sectors, all of which consume GaAs components. In the defense sector, UMS, an MMIC solution provider from the UK, creates a significant demand for GaAs components,” says Sunil.

The different domains of defense – radar, communication, and smart ammunition are supplied with designs done by UMS or their customers and are based on the UMS technology platform. However, this region will grow at a slower rate when compared to the other two segments as most semiconductor foundries and manufacturing units are present in APAC and the Americas.

The top vendors in the global GaAs market highlighted in the report are:

  • Skyworks Solutions
  • Qorvo
  • Broadcom

Physicists at the National Institute of Standards and Technology (NIST) have cooled a mechanical object to a temperature lower than previously thought possible, below the so-called “quantum limit.”

The new NIST theory and experiments, described in the Jan. 12, 2017, issue of Nature, showed that a microscopic mechanical drum–a vibrating aluminum membrane–could be cooled to less than one-fifth of a single quantum, or packet of energy, lower than ordinarily predicted by quantum physics. The new technique theoretically could be used to cool objects to absolute zero, the temperature at which matter is devoid of nearly all energy and motion, NIST scientists said.

“The colder you can get the drum, the better it is for any application,” said NIST physicist John Teufel, who led the experiment. “Sensors would become more sensitive. You can store information longer. If you were using it in a quantum computer, then you would compute without distortion, and you would actually get the answer you want.”

“The results were a complete surprise to experts in the field,” Teufel’s group leader and co-author José Aumentado said. “It’s a very elegant experiment that will certainly have a lot of impact.”

The drum, 20 micrometers in diameter and 100 nanometers thick, is embedded in a superconducting circuit designed so that the drum motion influences the microwaves bouncing inside a hollow enclosure known as an electromagnetic cavity. Microwaves are a form of electromagnetic radiation, so they are in effect a form of invisible light, with a longer wavelength and lower frequency than visible light.

The microwave light inside the cavity changes its frequency as needed to match the frequency at which the cavity naturally resonates, or vibrates. This is the cavity’s natural “tone,” analogous to the musical pitch that a water-filled glass will sound when its rim is rubbed with a finger or its side is struck with a spoon.

NIST scientists previously cooled the quantum drum to its lowest-energy “ground state,” or one-third of one quantum. They used a technique called sideband cooling, which involves applying a microwave tone to the circuit at a frequency below the cavity’s resonance. This tone drives electrical charge in the circuit to make the drum beat. The drumbeats generate light particles, or photons, which naturally match the higher resonance frequency of the cavity. These photons leak out of the cavity as it fills up. Each departing photon takes with it one mechanical unit of energy–one phonon–from the drum’s motion. This is the same idea as laser cooling of individual atoms, first demonstrated at NIST in 1978 and now widely used in applications such atomic clocks.

The latest NIST experiment adds a novel twist–the use of “squeezed light” to drive the drum circuit. Squeezing is a quantum mechanical concept in which noise, or unwanted fluctuations, is moved from a useful property of the light to another aspect that doesn’t affect the experiment. These quantum fluctuations limit the lowest temperatures that can be reached with conventional cooling techniques. The NIST team used a special circuit to generate microwave photons that were purified or stripped of intensity fluctuations, which reduced inadvertent heating of the drum.

“Noise gives random kicks or heating to the thing you’re trying to cool,” Teufel said. “We are squeezing the light at a ‘magic’ level–in a very specific direction and amount–to make perfectly correlated photons with more stable intensity. These photons are both fragile and powerful.”

The NIST theory and experiments indicate that squeezed light removes the generally accepted cooling limit, Teufel said. This includes objects that are large or operate at low frequencies, which are the most difficult to cool.

The drum might be used in applications such as hybrid quantum computers combining both quantum and mechanical elements, Teufel said. A hot topic in physics research around the world, quantum computers could theoretically solve certain problems considered intractable today.

Solar cells made with films mimicking the structure of the mineral perovskite are the focus of worldwide research. But only now have researchers at Case Western Reserve University directly shown the films bear a key property allowing them to efficiently convert sunlight into electricity.

Identifying that attribute could lead to more efficient solar panels.

Electrons generated when light strikes the film are unrestricted by grain boundaries — the edges of crystalline subunits within the film — and travel long distances without deteriorating, the researchers showed. That means electric charge carriers that become trapped and decay in other materials are instead available to be drawn off as current.

The scientists directly measured the distance traveled–called diffusion length — for the first time by using the technique called “spatially scanned photocurrent imaging microscopy.” Diffusion length within a well-oriented perovskite film measured up to 20 micrometers.

The findings, published in the journal Nano Letters, indicate that solar cells could be made thicker without harming their efficiency, said Xuan Gao, associate professor of physics and author of the paper.

“A thicker cell can absorb more light,” he said, “potentially yielding a better solar cell.”

Efficiency built in

Solar power researchers believe perovskite films hold great promise. In less than five years, films made with the crystalline structure have surpassed 20 percent efficiency in converting sunlight to electricity, a mark that took decades to reach with silicon-based solar cells used today.

In this research, Gao’s lab performed spatially scanned photocurrent image measurements on films made in the lab of Case Western Reserve chemistry professor Clemens Burda.

Perovskite minerals found in nature are oxides of certain metals, but Burda’s lab made organo-metallic films with the same crystalline structure using methyl ammonium lead tri-iodide (CH3NH3PBI3), a three-dimensional lead halide surrounded by small organic methyl ammonium molecules that hold the lattice structure together.

“The question has been, ‘How are these solar cells so efficient? If we would know, we could further improve perovskite solar cells” Burda said. “People thought it could be due to unusually long electron transport, and we directly measured it.”

Diffusion length is the distance an electron or its opposite, called a hole, travels from generation until it recombines or is extracted as electric current. The distance is the same as transport length when no electric field (which usually increases the distance traveled) is applied.

Measuring travel

The labs made repeated measurements by focusing a tiny laser spot on films 8 millimeters square by 300 nanometers thick. The films were made stable by coating the perovskite with a layer of the polymer parylene.

The light generates electrons and holes and the photocurrent, or stream of electrons, is recorded between the electrodes positioned about 120 microns away from each other while the film is scanned along two perpendicular directions. The scanning yields a two-dimensional spatial map of carrier diffusion and transport characteristics.

The measurements showed diffusion length averaged about 10 microns. In some cases, the length reached 20 microns, showing the functional area of the film is at least 20 microns long, the researchers said.

In some materials, grain boundaries decrease conductivity, but imaging showed that these interfaces between grains in the film exerted no influence on electron travel. Gao and Burda say this may be because grains in the film are well aligned, causing no impedance or other detrimental effects on electrons or holes.

Burda and Gao are now seeking federal funds to use the microscopy technique to determine whether different grain sizes, orientations, halide perovskite compositions, film thicknesses and more change the film’s properties, to further accelerate research in the field.

Air Products (NYSE:  APD) today announced it will increase nitrogen production to serve the growing demand of its existing customer in Pyeongtaek City, Gyeonggi Province, South Korea. It is Air Products’ second phase of capacity expansion to supply the semiconductor fab.

Air Products was awarded a major contract in 2015 for the supply of its industrial bulk gases and bulk specialty gas supply system. The company is undertaking a multi-phase expansion project involving multiple ultra high-purity nitrogen plants, hydrogen generators and a liquefier. In this phase, a second nitrogen plant will be built.

“We are pleased to bring additional nitrogen capacity to the semiconductor fab to support its  increasing demand,” said Kyo-Yung Kim, president of Air Products Korea. “Our latest expansion represents Air Products’ commitment to growing together with customers in the expanding region through continued investment. It will put us in an even stronger position to deliver our safe and reliable industrial gas solutions in a very cost-effective way.”

An integrated gases supplier for the global electronics industry, Air Products has more than 40 years of experience in the safe and reliable delivery of gases to a variety of markets, including some of the world’s biggest technology companies. Air Products is working with these industry leaders to develop the next generation of semiconductors and displays for tablets, computers and mobile devices.

In the past decade, two-dimensional, 2D, materials have captured the fascination of a steadily increasing number of scientists. These materials, whose defining feature is having a thickness of only one to very few atoms, can be made of a variety of different elements or combinations thereof. Scientists’ enchantment with 2D materials began with Andre Geim and Konstantin Novoselov’s Nobel Prize winning experiment: creating a 2D material using a lump of graphite and common adhesive tape. This ingeniously simple experiment yielded an incredible material: graphene. This ultra-light material is roughly 200 times stronger than steel and is a superb conductor. Once scientists discovered that graphene had more impressive properties than its bulk component graphite, they decided to investigate other 2D materials to see if this was a universal property.

Christopher Petoukhoff, a Rutgers University graduate student working in the Femtosecond Spectroscopy Unit at the Okinawa Institute of Science and Technology Graduate University (OIST), studies a 2D material, made of molybdenum disulfide (MoS2). His research focuses on the 2D material’s optoelectronic applications, or how the material can detect and absorb light. Optoelectronics are ubiquitous in today’s world, from the photodetectors in automatic doors and hand dryers, to solar cells, to LED lights, but as anyone who has stood in front of an automatic sink desperately waving their hands around to get it to work will tell you, there is plenty of room for improvement. The 2D MoS2 is particularly interesting for use in photodetectors because of its capability of absorbing the same amount of light as 50nm of the currently used silicon-based technologies, while being 70 times thinner.

Petoukhoff, under the supervision of Professor Keshav Dani, seeks to improve optoelectronic devices by adding a 2D layer of MoS2 to an organic semiconductor, which has similar absorption strengths as MoS2. The theory behind using both materials is that the interaction between the MoS2 layer and the organic semiconductor should lead to efficient charge transfer. Petoukhoff’s research, published in ACS Nano, demonstrates for the first time that charge transfer between these two layers occurs at an ultra-fast timescale, on the order of less than 100 femtoseconds, or one tenth of one millionth of one millionth of a second.

The thinness of these materials, however, becomes a limiting factor in their efficiency as photovoltaics, or light-energy conversion devices. Light absorbing devices, such as solar cells and photodetectors, require a certain amount of optical thickness in order to absorb photons, rather than allowing them to pass through. To overcome this, researchers from the Femtosecond Spectroscopy Unit added an array of silver nanoparticles, or a plasmonic metasurface, to the organic semiconductor-MoS2 hybrid to focus and localize the light in the device. The addition of the metasurface increases the optical thickness of the material while capitalizing on the unique properties of the ultra-thin active layer, which ultimately increase the total absorption.

While this research is still in its infancy, its implications for the future are huge. Combinations with 2D materials have the potential to revolutionize the marketability of optoelectronic devices. Conventional optoelectronic devices are expensive to manufacture and are often made from scarce or toxic elements, such as indium or arsenic. Organic semiconductors have low manufacturing costs, and are made of earth-abundant and non-toxic elements. This research can potentially improve the cost and efficiency of optoelectronics, leading to better products in the future.

A team of researchers at the University of Illinois at Urbana-Champaign has advanced gallium nitride (GaN)-on-silicon transistor technology by optimizing the composition of the semiconductor layers that make up the device. Working with industry partners Veeco and IBM, the team created the high electron mobility transistor (HEMT) structure on a 200 mm silicon substrate with a process that will scale to larger industry-standard wafer sizes.

Can Bayram, an assistant professor of electrical and computer engineering (ECE), and his team have created the GaN HEMT structure on a silicon platform because it is compatible with existing CMOS manufacturing processes and is less expensive than other substrate options like sapphire and silicon carbide.

However, silicon does have its challenges. Namely, the lattice constant, or space between silicon atoms, doesn’t match up with the atomic structure of the GaN grown on top of it.

“When you grow the GaN on top, there’s a lot of strain between the layers, so we grew buffer layers [between the silicon and GaN] to help change the lattice constant into the proper size,” explained ECE undergraduate researcher Josh Perozek, lead author of the group’s paper, “Investigation of structural, optical, and electrical characteristics of an AlGaN/GaN high electron mobility transistor structure across a 200mm Si(1 1 1) substrate,” in the Journal of Physics D: Applied Physics.

Without these buffer layers, cracks or other defects will form in the GaN material, which would prevent the transistor from operating properly. Specifically, these defects — threading dislocations or holes where atoms should be–ruin the properties of the 2-dimensional electron gas channel in the device. This channel is critical to the HEMTs ability to conduct current and function at high frequencies.

“The single most important thing for these GaN [HEMT] devices is to have high 2D electron gas concentration,” said Bayram, about the accumulation of electrons in a channel at the interface between the silicon and the various GaN-based layers above it.

“The problem is you have to control the strain balance among all those layers–from substrate all the way up to the channel — so as to maximize the density of the of the conducting electrons in order to get the fastest transistor with the highest possible power density.”

After studying three different buffer layer configurations, Bayram’s team discovered that thicker buffer layers made of graded AlGaN reduce threading dislocation, and stacking those layers reduces stress. With this type of configuration, the team achieved an electron mobility of 1,800 cm2/V-sec.

“The less strain there is on the GaN layer, the higher the mobility will be, which ultimately corresponds to higher transistor operating frequencies,” said Hsuan-Ping Lee, an ECE graduate student researcher leading the scaling of these devices for 5G applications.

According to Bayram, the next step for his team is to fabricate fully functional high-frequency GaN HEMTs on a silicon platform for use in the 5G wireless data networks.

When it’s fully deployed, the 5G network will enable faster data rates for the world’s 8 billion mobile phones, and will provide better connectivity and performance for Internet of Things (IoT) devices and driverless cars.

Atomera Incorporated (NASDAQ: ATOM), a semiconductor materials and intellectual property licensing company focused on deploying its proprietary technology into the semiconductor industry, today announced a master R&D service agreement with TSI Semiconductors, a specialty foundry with ISO, Automotive and Industrial Class Certifications. Atomera will leverage its significant investments in Mears Silicon Technology™ (MST®), and the manufacturing capability of TSI to accelerate fab integration and shorten time to market for its More-than-Moore architectural and material innovation.

“As a developer of advanced semiconductor materials, Atomera is constantly seeking to provide better electronic performance by enhancing transistors with our quantum engineered material innovations,” said Scott Bibaud, Atomera President and CEO. “Our foundry agreement with TSI significantly cuts fab cycle times, allowing for faster product development, test, and integration, and should accelerate our time to market with both existing and new customers. I could not be more excited by the dramatic improvement in development time our relationship with TSI allows.”

“TSI’s Technology Development Services are a perfect fit for cutting edge semiconductor technology companies like Atomera,” said Bruce Gray, Chief Executive Officer at TSI. “Their strong IP portfolio of new semiconductor materials such as MST®, combined with our 200mm fabrication capabilities and our focus on custom solutions and commercialization services, forms a partnership that showcases our capabilities and fast tracks Atomera’s development.”

This partnership allows Atomera to execute cycles of learning 5 to 10 times faster as compared to the engineering evaluation process experienced at foundries or integrated device manufacturers currently testing MST®. As a result, adoption of Atomera’s technology in the industry can be significantly accelerated. With MST® technology, manufacturers can address their yield, power and performance challenges at a fraction of the cost of alternative approaches. Atomera breathes new life into semiconductor fabs by providing up to a full node of performance benefits to existing fab processes enabling significantly better performance in today’s electronics. Atomera’s patented material technology enables more efficient and better controlled current flow, leading to dramatic improvements in device performance and power efficiency.

Atomera will be holding meetings with customers, analysts, media and investors during the 2017 Consumer Electronics Show (“CES”) January 5-7, 2017 in Las Vegas at the Bellagio Hotel.

Germanium may not be a household name like silicon, its group-mate on the periodic table, but it has great potential for use in next-generation electronics and energy technology.

Of particular interest are forms of germanium that can be synthesized in the lab under extreme pressure conditions. However, one of the most-promising forms of germanium for practical applications, called ST12, has only been created in tiny sample sizes–too small to definitively confirm its properties.

“Attempts to experimentally or theoretically pin down ST12-germanium’s characteristics produced extremely varied results, especially in terms of its electrical conductivity,” said Carnegie’s Zhisheng Zhao, the first author on a new paper about this form of germanium.

The study’s research team, led by Carnegie’s Timothy Strobel, was able to create ST12-germanium in a large enough sample size to confirm its characteristics and useful properties. Their work is published by Nature Communications.

“This work will be of interest to a broad range of readers in the field of materials science, physics, chemistry, and engineering,” explained Carnegie’s Haidong Zhang, the co-leading author.

ST12-germanium has a tetragonal structure–the nameST12 means “simple tetragonal with 12 atoms.”(See illustration below.) It was created by putting germanium under about 138 times normal atmospheric pressure (14 gigapascals) and then decompressing it slowly at room temperature.

The millimeter-sized samples of ST12-germanium that the team created were large enough that they could be studied using a variety of spectroscopic techniques in order to confirm its long-debated characteristics.

Like the most common, diamond-cubic form of germanium, they found that ST12 is a semiconductor with a so-called indirect band gap. Metallic substances conduct electrical current easily, whereas insulating materials conduct no current at all. Semiconducting materials exhibit mid-range electrical conductivity. When semiconducting materials are subjected to an input of a specific energy, bound electrons can be moved to higher-energy, conducting states. The specific energy required to make this jump to the conducting state is defined as the “band gap.” While direct band gap materials can effectively absorb and emit light, indirect band gap materials cannot.

“Our team was able to quantify ST12’s optical band gap–where visible light energy can be absorbed by the material–as well as its electrical and thermal properties, which will help define its potential for practical applications,” Strobel said. “Our findings indicate that due to the size of its band gap, ST12-germanium may be a better material for infrared detection and imaging technology than the diamond-cubic form of the element already being used for these purposes.”