Category Archives: Packaging Materials

Cree, Inc. (NASDAQ: CREE) announces that it signed a non-exclusive, worldwide, royalty-bearing patent license agreement with Nexperia BV, a Dutch company. The agreement provides Nexperia access to Cree’s extensive gallium nitride (GaN) power device patent portfolio, which includes over 300 issued U.S. and foreign patents that describe inventive aspects of high electron mobility transistor (HEMT) and GaN Schottky diode devices. The portfolio addresses novel device structures, materials and processing improvements, and packaging technology. The patent license involves no transfer of technology.

“Cree was founded to develop novel compound semiconductor materials like GaN and SiC and to create devices that capitalize on their unique properties,” said John Palmour, Cree co-founder and CTO of Wolfspeed, a Cree company. “Cree’s decades of innovation are now yielding devices that enable market introductions of new power management and wireless systems. To help facilitate the growth of these new markets, Cree is licensing its GaN power device patents for GaN power-management systems.”

Graphene, a two-dimensional lattice of carbon atoms, has attracted enormous interest from a broad base of the research community for more than one decade. Graphene nanoribbons (GNRs), narrow strips of graphene, being quasi one-dimensional, possess complementary features relative to their two-dimensional counterpart of graphene sheets. Based on theoretical calculations, GNRs’ electrical properties can be controlled by the width and edge configuration and they can vary from being metallic to semiconducting. The physical properties of the GNRs depend significantly on the size and number of layers, which in turn depend on their synthesis method. There are three major approaches for synthesis of GNRs: cutting graphene by different lithographic techniques; bottom-up synthesis from polycyclic molecules; and unzipping of carbon nanotubes (CNTs). While the bottom-up method provides a route to precise edge control, and the lithographic method can afford GNRs with precise placement, the unzipping method has the advantage of mass-production on a large scale.

MWCNT unzipping methods can be classified into four major types: the reductive-intercalation-assisted approach, the oxidative unzipping, the electrochemical unzipping, and the group of methods that can be denoted as miscellaneous. The first approach is based on the well-known ability of alkali metals to intercalate graphite with expansion in the Z-axis direction. Being applied toward MWCNTs, such lattice expansion induces extreme stress within the concentric walls, resulted in the bursting, or longitudinal opening, of the tubes. The resulted GNRs are highly conductive, but they remain multi-layered and foliated. Due to the attraction between the surfaces, they do not exfoliate to single-layer ribbons.

The oxidative approach involves treatment of MWCNTs in acidic oxidative media with the formulation almost identical to that used in production of graphene oxide (GO) from graphite by the Hummers method. The resulting product is graphene oxide nanoribbons (GONRs). Unlike GNRs obtained by the reductive-intercalation method, GONRs easily exfoliate in aqueous solution, and they can be obtained as single-layered structures. A reaction mechanism for oxidative unzipping was proposed by Kosynkin et al.1 Invoking the classical oxidation of the alkenes by permanganate in acids, the first step is the formation of manganate ester on a C-C bond, and the second step is the rupture of the C-C bond with formation of ketones at the newly formed edges. This mechanism was further developed in the theoretical work by Rangel et al.2 The original synthesis spawned numerous studies on oxidative unzipping of MWCNTs. In many reports, the unzipping process was denoted as “chemical” as opposed to the “intercalation-exfoliation”, indicating that the permanganate-induced oxidative mechanism has been commonly accepted, and was even suggested toward unzipping SWCNTs.

The newly proposed mechanism was based on the Lab’s competences on the studies of the mechanism of GO formation of graphite that involves three consecutive steps: (a) intercalation of graphite by sulfuric acid with formation of a stage-1 H2SO4-graphite intercalation compound (GIC); (b) conversion of stage-1 H2SO4-GIC into pristine GO, and (c) exfoliation of GO to single-layer sheets upon exposure to water. Thus, under given conditions, formation of stage-1 H2SO4-GIC is unavoidable for any graphitic material. Subsequently, the mechanism of the oxidative unzipping of MWCNTs might be also intercalation-driven. If this is correct, one should be able to stop the reaction after the first intercalation-unzipping step before the second oxidation step proceeds. If attained, this will afford unzipped but not oxidized or minimally oxidized products possessing properties similar to reductively unzipped GNRs obtained by potassium or sodium-potassium metal intercalation. In this work, the Lab investigated the impact of the two key parameters, the KMnO4/MWCNT ratio, and the time of reaction on the structure and composition of as-obtained GNR products, and derived a revised and more complete understanding of the unzipping process.

The researchers demonstrated that the mechanism of the oxidative unzipping of MWCNTs is indeed intercalation-driven. The overall unzipping process involves the same three steps as in the course of GO production from graphite by the Hummers and modified Hummers methods: intercalation, oxidation, and exfoliation. With MWCNTs, the intercalation is associated with simultaneous unzipping. At low KMnO4/MWCNT ratios, one can obtain GNRs with characteristics similar to those produced by reductive unzipping. 0.12 wt equiv KMnO4 is the threshold ratio sufficient for almost complete unzipping, with only small amounts of covalent oxidation. Controlling the KMnO4/MWCNT ratio and time of reaction allows one to produce GNRs with the properties varying in a broad continuous range from multi-layered graphenic GNRs through single-layered GONRs. Thus, the team answered several questions that remained open in the field of unzipping MWCNTs, such as the reason why the inner-most walls of the nanotubes remain zipped. The intercalation-driven reaction mechanism provides a rationale for the impossibility of unzipping single-wall and few-wall CNTs, and aids in a reevaluation of the data from the oxidative unzipping process.

Indium Corporation, one of more than 3,000 ON Semiconductor production suppliers, was selected for its commitment to ensuring high quality and supply continuity in an evolving semiconductor market.

The annual Perfect Quality Award was presented to Weng Fai Pang, Managing Director for Asia-Pacific Operations, and Tim Twining, Vice President of Marketing, at ON Semiconductor’s Supplier Executive Conference in March in Hong Kong, China.

Indium Corporation is a materials manufacturer and supplier to the global electronics, semiconductor, thin-film, and thermal management markets. Products include solders and fluxes; brazes; thermal interface materials; sputtering targets; indium, gallium, germanium, and tin metals and inorganic compounds; and NanoFoil®. Founded in 1934, the company has global technical support and factories located in China, Malaysia, Singapore, South Korea, the United Kingdom, and the USA.

When power generators like windmills and solar panels transfer electricity to homes, businesses and the power grid, they lose almost 10 percent of the generated power. To address this problem, scientists are researching new diamond semiconductor circuits to make power conversion systems more efficient.

The view of the H-diamond MOSFET NOR logic circuit from above (left), and the operation of the NOR logic circuits, showing that the circuit only produces voltage when both inputs are at zero. Credit: Liu et al.

The view of the H-diamond MOSFET NOR logic circuit from above (left), and the operation of the NOR logic circuits, showing that the circuit only produces voltage when both inputs are at zero. Credit: Liu et al.

A team of researchers from Japan successfully fabricated a key circuit in power conversion systems using hydrogenated diamond (H-diamond.) Furthermore, they demonstrated that it functions at temperatures as high as 300 degrees Celsius. These circuits can be used in diamond-based electronic devices that are smaller, lighter and more efficient than silicon-based devices. The researchers report their findings this week in Applied Physics Letters, from AIP Publishing.

Silicon’s material properties make it a poor choice for circuits in high-power, high-temperature and high-frequency electronic devices. “For the high-power generators, diamond is more suitable for fabricating power conversion systems with a small size and low power loss,” said Jiangwei Liu, a researcher at Japan’s National Institute for Materials Science and a co-author on the paper.

In the current study, researchers tested an H-diamond NOR logic circuit’s stability at high temperatures. This type of circuit, used in computers, gives an output only when both inputs are zero. The circuit consisted of two metal-oxide-semiconductor field-effect transistors (MOSFETs), which are used in many electronic devices, and in digital integrated circuits, like microprocessors. In 2013, Liu and his colleagues were the first to report fabricating an E-mode H-diamond MOSFET.

When the researchers heated the circuit to 300 degrees Celsius, it functioned correctly, but failed at 400 degrees. They suspect that the higher temperature caused the MOSFETs to breakdown. Higher temperatures may be achievable however, as another group reported successful operation of a similar H-diamond MOSFET at 400 degrees Celsius. For comparison, the maximum operation temperature for silicon-based electronic devices is about 150 degrees.

In the future, the researchers plan to improve the circuit’s stability at high temperatures by altering the oxide insulators and modifying the fabrication process. They hope to construct H-diamond MOSFET logic circuits that can operate above 500 degrees Celsius and at 2.0 kilovolts.

“Diamond is one of the candidate semiconductor materials for next-generation electronics, specifically for improving energy savings,” said Yasuo Koide, a director at the National Institute for Materials Science and co-author on the paper. “Of course, in order to achieve industrialization, it is essential to develop inch-sized single-crystal diamond wafers and other diamond-based integrated circuits.”

By Jamie Girard, Sr. Director, Public Policy, SEMI

Although many months past due, Congress on March 23 finalized the federal spending for the remainder of fiscal year (FY) 2018, only hours before a what would have been the third government shutdown of the year. Congressional spending has been allocated in fits and starts since the end of FY 2017 last September, with patchwork deals keeping things running amid pervasive uncertainty. While this clearly isn’t an ideal way to fund the federal government, the end result will make many in the business of research and development pleased with the addition of more resources for science and innovation.

There was grave concern over the future of federal spending with the release of the president’s FY 2018 budget, which would have cut the National Science Foundation (NSF) budget by 11 percent and National Institutes of Standards & Technology (NIST) spending by 30 percent. Relief came with early drafts from Congress that whittled those cuts down to between 2-9 percent. But the real boost was a February bipartisan Congressional agreement that lifted self-imposed spending caps and introduced a generous dose of non-defense discretionary spending, increasing NSF spending 3.9 percent over the previous year and the NIST budget an astounding 25.9 percent over FY 2017 levels.

SEMI applauds this much-needed support for basic research and development (R&D) at these agencies after their budgets were cut or flat-funded for multiple cycles. It is well understood that federal R&D funding is critical to U.S. competitiveness and future economic prosperity. With the stakes that high, full funding of R&D programs at the NSF and NIST should be a bipartisan national priority backed by a strong and united community of stakeholders and advocates in the business, professional, research, and education communities.

With the work for FY 2018 completed, Congress will now turn to FY 2019 spending – already behind schedule due to the belated completion of the previous year’s budget. With 2018 an election year, Congress will likely begin work on the FY 2019 budget in short order, but probably won’t complete its work prior to the November elections.  SEMI will continue to work with lawmakers to support the R&D budgets at the agencies and their important basic science research. If you’d like to know how you can be more involved with SEMI’s public policy work, please contact Jamie Girard, Sr. Director, Public Policy at [email protected].

Graphene is a two-dimensional nanocarbon material, having unique properties in electronic, optical and thermal properties, which can be applied for optoelectronic devices. Graphene-based blackbody emitters are also promising light emitters on silicon chip in NIR and mid-infrared region. However, although graphene-based blackbody emitters have been demonstrated under steady-state conditions or relatively slow modulation (100 kHz), the transient properties of these emitters under high-speed modulation have not been reported to date. Also, the optical communications with graphene-based emitters have never been demonstrated.

Square graphene sheet is connected to source and drain electrodes. Modulated blackbody emission is obtained from graphene by applying input signal. Credit: Keio University

Square graphene sheet is connected to source and drain electrodes. Modulated blackbody emission is obtained from graphene by applying input signal. Credit: Keio University

Here, a highly integrated, high-speed and on-chip blackbody emitter based on graphene in NIR region including telecommunication wavelength was demonstrated. A fast response time of ~ 100 ps, which is ~ 105 higher than the previous graphene emitters, has been experimentally demonstrated for single and few-layer graphene, the emission responses can be controlled by the graphene contact with the substrate depending on the number of graphene layers. The mechanisms of the high-speed emission are elucidated by performing theoretical calculations of the heat conduction equations considering the thermal model of emitters including graphene and a substrate. The simulated results indicate that the fast response properties can be understood not only by the classical thermal transport of in-plane heat conduction in graphene and heat dissipation to the substrate but also by the remote quantum thermal transport via the surface polar phonons (SPoPhs) of the substrates. In addition, first real-time optical communication with graphene-based light emitters was experimentally demonstrated, indicating that graphene emitters are novel light sources for optical communication. Furthermore, we fabricated integrated two-dimensional array emitters with large-scale graphene grown by chemical vapour deposition (CVD) method and capped emitters operable in air, and carried out the direct coupling of optical fibers to the emitters owing to their small footprint and planar device structure.

Graphene light emitters are greatly advantageous over conventional compound semiconductor emitters because they can be highly integrated on silicon chip due to simple fabrication processes of graphene emitters and direct coupling with silicon waveguide through an evanescent field. Because graphene can realize high-speed, small footprint and on-Si-chip light emitters, which are still challenges for compound semiconductors, the graphene-based light emitters can open new routes to highly integrated optoelectronics and silicon photonics.

Single crystal tin selenide (SnSe) is a semiconductor and an ideal thermoelectric material; it can directly convert waste heat to electrical energy or be used for cooling. When a group of researchers from Case Western Reserve University in Cleveland, Ohio, saw the graphene-like layered crystal structure of SnSe, they had one of those magical “aha!” moments.

Electric charges in a nanostructured tin selenide (SnSe) thin film flow from the hot end to the cold end of the material and generate a voltage. Credit: Xuan Gao

Electric charges in a nanostructured tin selenide (SnSe) thin film flow from the hot end to the cold end of the material and generate a voltage. Credit: Xuan Gao

The group reports in the Journal of Applied Physics, from AIP Publishing, that they immediately recognized this material’s potential to be fabricated in nanostructure forms. “Our lab has been working on two-dimensional semiconductors with layered structures similar to graphene,” said Xuan Gao, an associate professor at Case Western.

Nanomaterials with nanometer-scale dimensions — such as thickness and grain size — have favorable thermoelectric properties. This inspired the researchers to grow nanometer-thick nanoflakes and thin films of SnSe to further study its thermoelectric properties.

The group’s work centers on the thermoelectric effect. They study how the temperature difference in a material can cause charge carriers — electrons or holes — to redistribute and generate a voltage across the material, converting thermal energy into electricity.

“Applying a voltage on a thermoelectric material can also lead to a temperature gradient, which means you can use thermoelectric materials for cooling,” said Gao. “Generally, materials with a high figure of merit have high electrical conductivity, a high Seebeck coefficient — generated voltage per Kelvin of temperature difference within a material — and low thermal conductivity,” he said.

A thermoelectric figure of merit, ZT, indicates how efficiently a material converts thermal energy to electrical energy. The group’s work focuses on the power factor, which is proportional to ZT and indicates a material’s ability to convert energy, so they measured the power factor of the materials they made.

To grow SnSe nanostructures, they used a chemical vapor deposition (CVD) process. They thermally evaporated a tin selenide powder source inside an evacuated quartz tube. Tin and selenium atoms react on a silicon or mica growth wafer placed at the low-temperature zone of the quartz tube. This causes SnSe nanoflakes to form on the surface of the wafer. Adding a dopant element like silver to SnSe thin films during material synthesis can further optimize its thermoelectric properties.

At the start, “the nanostructure SnSe thin films we fabricated had a power factor of only ~5 percent of that of single crystal SnSe at room temperature,” said Shuhao Liu, an author on the paper. But, after trying a variety of dopants to improve the material’s power factor, they determined that “silver was the most effective — resulting in a 300 percent power factor improvement compared to undoped samples,” Liu said. “The silver-doped SnSe nanostructured thin film holds promise for a high figure of merit.”

In the future, the researcher hope that SnSe nanostructures and thin films may be useful for miniaturized, environmentally friendly, low-cost thermoelectric and cooling devices.

Data is only as good as humans’ ability to analyze and make use of it.

In materials research, the ability to analyze massive amounts of data–often generated at the nanoscale–in order to compare materials’ properties is key to discovery and to achieving industrial use. Jeffrey M. Rickman, a professor of materials science and physics at Lehigh University, likens this process to candy manufacturing:

“If you are looking to create a candy that has, say, the ideal level of sweetness, you have to be able to compare different potential ingredients and their impact on sweetness in order to make the ideal final candy,” says Rickman.

For several decades, nanomaterials–matter that is so small it is measured in nanometers (one nanometer = one-billionth of a meter) and can be manipulated at the atomic scale–have outperformed conventional materials in strength, conductivity and other key attributes. One obstacle to scaling up production is the fact that scientists lack the tools to fully make use of data–often in the terabytes, or trillions of bytes–to help them characterize the materials–a necessary step toward achieving “the ideal final candy.”

What if such data could be easily accessed and manipulated by scientists in order to find real-time answers to research questions?

The promise of materials like DNA-wrapped single-walled carbon nanotubes could be realized. Carbon nanotubes are a tube-shaped material which can measure as small as one-billionth of a meter, or about 10,000 times smaller than a human hair. This material could revolutionize drug delivery and medical sensing with its unique ability to penetrate living cells.

A new paper takes a step toward realizing the promise of such materials. Authored by Rickman, the article describes a new way to map material properties relationships that are highly multidimensional in nature. Rickman employs methods of data analytics in combination with a visualization strategy called parallel coordinates to better represent multidimensional materials data and to extract useful relationships among properties. The article, “Data analytics and parallel-coordinate materials property charts,” has been published in npj Computational Materials, a Nature Research journal.

“In the paper,” says Rickman, “we illustrate the utility of this approach by providing a quantitative way to compare metallic and ceramic properties–though the approach could be applied to any materials you want to compare.”

It is the first paper to come out of Lehigh’s Nano/Human Interface Presidential Engineering Research Initiative, a multidisciplinary research initiative that proposes to develop a human-machine interface to improve the ability of scientists to visualize and interpret the vast amounts of data that are generated by scientific research. It was kickstarted by a $3-million institutional investment announced last year.

The leader of the initiative is Martin P. Harmer, professor of materials science and engineering. In addition to Rickman, other senior faculty members include Anand Jagota, department chair of bioengineering; Daniel P. Lopresti, department chair of computer science and engineering and director of Lehigh’s Data X Initiative; and Catherine M. Arrington, associate professor of psychology.

“Several research universities are making major investments in big data,” says Rickman. “Our initiative brings in a relatively new aspect: the human element.”

According to Arrington, the Nano/Human Interface initiative emphasizes the human because the successful development of new tools for data visualization and manipulation must necessarily include a consideration of the cognitive strengths and limitations of the scientist.

“The behavioral and cognitive science aspects of the Nano/Human Interface initiative are twofold,” says Arrington. “First, a human-factors research model allows for analysis of the current work environment and clear recommendations to the team for the development of new tools for scientific inquiry. Second, a cognitive psychology approach is needed to conduct basic science research on the mental representations and operations that may be uniquely challenged in the investigation of nanomaterials.”

Rickman’s proposed method uses parallel coordinates, which is a method of visualizing data that makes it possible to spot outliers or patterns based on related metric factors. Parallel coordinates charts can help tease out those patterns.

The challenge, says Rickman, lies in interpreting what you see.

“If plotting points in two dimensions using X and Y axes, you might see clusters of points and that would tell you something or provide a clue that the materials might share some attributes,” he explains. “But, what if the clusters are in 100 dimensions?”

According to Rickman, there are tools that can help cut down on numbers of dimensions and eliminate non-relevant dimensions to help one better identify these patterns. In this work, he applies such tools to materials with success.

“The different dimensions or axes describe different aspects of the materials, such as compressibility and melting point,” he says.

The charts described in the paper simplify the description of high-dimensional geometry, enable dimensional reduction and the identification of significant property correlations and underline distinctions among different materials classes.

From the paper: “In this work, we illustrated the utility of combining the methods of data analytics with a parallel coordinates representation to construct and interpret multidimensional materials property charts. This construction, along with associated materials analytics, permits the identification of important property correlations, quantifies the role of property clustering, highlights the efficacy of dimensional reduction strategies, provides a framework for the visualization of materials class envelopes and facilitates materials selection by displaying multidimensional property constraints. Given these capabilities, this approach constitutes a powerful tool for exploring complex property interrelationships that can guide materials selection.”

Returning to the candy manufacturing metaphor, Rickman says: “We are looking for the best methods of putting the candies together to make what we want and this method may be one way of doing that.”

New frontier, new approaches

Creating a roadmap to finding the best methods is the aim of a 2½-day, international workshop called “Workshop on the Convergence of Materials Research and Multi-Sensory Data Science” that is being hosted by Lehigh University in partnership with The Ohio State University.

The workshop–which will take place at Bear Creek Mountain Resort in Macungie, PA from June 11-13, 2018–will bring together scientists from allied disciplines in the basic and social sciences and engineering to address many issues involved in multi-sensory data science as applied to problems in materials research.

“We hope that one outcome of the workshop will be the forging of ongoing partnerships to help develop a roadmap to establishing a common language and framework for continued dialogue to move this effort of promoting multi-sensory data science forward,” says Rickman, who is Principal Investigator on an National Science Foundation (NSF) grant, awarded by the Division of the Materials Research in support of the workshop.

Co-Principal Investigator, Nancy Carlisle, assistant professor in Lehigh’s Department of Psychology, says the conference will bring together complementary areas of expertise to allow for new perspectives and ways forward.

“When humans are processing data, it’s important to recognize limitations in the humans as well as the data,” says Carlisle. “Gathering information from cognitive science can help refine the ways that we present data to humans and help them form better representations of the information contained in the data. Cognitive scientists are trained to understand the limits of human mental processing- it’s what we do! Taking into account these limitations when devising new ways to present data is critical to success.”

Adds Rickman: “We are at a new frontier in materials research, which calls for new approaches and partners to chart the way forward.”

Working up a sweat from carrying a heavy load? That is when the textile works at its best. Researchers at Chalmers University of Technology have developed a fabric that converts kinetic energy into electric power, in cooperation with the Swedish School of Textiles in Borås and the research institute Swerea IVF. The greater the load applied to the textile and the wetter it becomes the more electricity it generates. The results are now published in the Nature Partner journal Flexible Electronics.

Chalmers researchers Anja Lund and Christian Müller have developed a woven fabric that generates electricity when it is stretched or exposed to pressure. The fabric can currently generate enough power to light an LED, send wireless signals or drive small electric units such as a pocket calculator or a digital watch.

The technology is based on the piezoelectric effect, which results in the generation of electricity from deformation of a piezoelectric material, such as when it is stretched. In the study the researchers created a textile by weaving a piezoelectric yarn together with an electrically conducting yarn, which is required to transport the generated electric current.

“The textile is flexible and soft and becomes even more efficient when moist or wet,” Lund says. “To demonstrate the results from our research we use a piece of the textile in the shoulder strap of a bag. The heavier the weight packed in the bag and the more of the bag that consists of our fabric, the more electric power we obtain. When our bag is loaded with 3 kilos of books, we produce a continuous output of 4 microwatts. That’s enough to intermittently light an LED. By making an entire bag from our textile, we could get enough energy to transmit wireless signals.”

The piezoelectric yarn is made up of twenty-four fibres, each as thin as a strand of hair. When the fibres are sufficiently moist they become enclosed in liquid and the yarn becomes more efficient, since this improves the electrical contact between the fibres. The technology is based on previous studies by the researchers in which they developed the piezoelectric fibres, to which they have now added a further dimension.

“The piezoelectric fibres consist of a piezoelectric shell around an electrically conducting core,” Lund says. “The piezoelectric yarn in combination with a commercial conducting yarn constitute an electric circuit connected in series.”

Previous work by the researchers on piezoelectric textiles has so far mainly focused on sensors and their ability to generate electric signals through pressure sensitivity. Using the energy to continuously drive electronic components is unique.

“Woven textiles from piezoelectric yarns makes the technology easily accessible and it could be useful in everyday life. It’s also possible to add more materials to the weave or to use it as a layer in a multi-layer product. It requires some modification, but it’s possible,” Lund says.

The researchers consider that the technology is, in principle, ready for larger scale production. It is now mainly up to industrial product developers to find out how to make use of the technology. Despite the advanced technology underlying the material, the cost is relatively low and is comparable with the price of Gore-Tex. Through their collaboration with the Swedish School of Textiles in Borås the researchers have been able to demonstrate that the yarn can be woven in industrial looms and is sufficiently wear-resistant to cope with the harsh conditions of mass production.

Magnolia Optical Technology, Inc. announced that it is working with the Defense Advanced Research Projects Agency (DARPA) under the Phase II SBIR Program for Development of High-Performance Thin-Film Solar Cells for Portable Power Applications (Contract No D15PC00222).

Photovoltaic devices can provide a portable source of electrical power for a wide variety of defense and commercial applications, including mobile power for dismounted soldiers, unmanned aerial vehicles, and remote sensors.

“The goal of the current program is to develop high-efficiency GaAs-based solar cells that maintain their performance over changing environmental conditions, and that are thinner and thus more cost-effective to produce,” said Dr. Roger Welser, Magnolia’s Chief Technical Officer. “By combining thin III-V absorbers with advanced light-trapping structures, single-junction GaAs-based devices provide a means to deliver high efficiency performance over a wide range of operating conditions at a fraction of the cost of the multi-junction structures typically employed for space power. In addition, the incorporation of nano-enhanced III-V absorbers provides a pathway to extend infrared absorption and increase the photovoltaic power conversion efficiency of cost-effective thin-film solar cells.”

Dr. Ashok Sood, President of Magnolia stated “changes in the solar spectrum can dramatically degrade the performance of traditional multi-junction devices – changes that occur naturally throughout the day, from season to season, and from location to location as sunlight passes through the earth’s atmosphere. Moreover, multi-junction III-V cells require thick, complex epitaxial layers and are therefore inherently expensive to manufacture. The technology under development as part of this DARPA-funded program addresses these key weaknesses in the established high-performance photovoltaic technology. The photovoltaic market is a rapidly growing segment of the energy industry with a wide range of commercial and defense applications.”

Magnolia specializes in developing optical technologies for defense and commercial applications. Based in Woburn, MA, Magnolia develops both thin film and nanostructure-based technologies that cover the ultraviolet, visible, and infrared part of the spectrum. These technologies are developed for use in advanced military sensors and other commercial applications including solar cells.