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Solar-Tectic LLC (“ST”) announced today that a patent application for a method of making III-V thin-film tandem solar cells with high performance has been allowed by the US Patent and Trademark Office. The patent, the first ever for a thin III-V layer on crystalline silicon thin-film, covers group III-V elements such as Gallium Arsenide (GaAs), and Indium Gallium Phosphide (InGaP), for the top layer, as well as all inorganic materials, including, silicon, germanium, etc., for the bottom layer.  Group III-V compounds such as Gallium Arsenide (GaAs) are proven photovoltaic materials with high efficiencies but until now have been cost prohibitive because high quality III-V material such as GaAs is expensive. Moreover, the cost of substrates on which to grow III-V materials, such as germanium, which is known to be an ideal material, has kept the technology from market entry. In the breakthrough technology here, ultra-thin films of III-V materials and silicon (or germanium) replace expensive, thicker wafers thereby lowering the costs dramatically. The inventor is Ashok Chaudhari, CEO of Solar-Tectic LLC.

III-V tandem (or multi-junction) cells built on wafers such as silicon are currently being developed in labs, with high efficiencies of around ~30%.  The highest dual-junction cell efficiency (32.8%) came from a tandem cell that stacked a layer of gallium arsenide (GaAs) atop crystalline silicon. Manufacturing costs are expensive especially if a germanium wafer is used as the bottom material in the two layer tandem structure.  In order to compete with low cost silicon wafer technology which is 90% of the global solar panel market, efficiencies must not only be as high as silicon wafers or greater (21.7% and 26.7% are lab records for poly- and monocrystalline silicon wafer cells, respectively), but manufacturing costs must also be lower. This is achievable in the Solar-Tectic LLC patented technology, which uses common industrial manufacturing processes and at low temperature. There is no wafer involved which saves material and energy; instead a thin film allows for precise control of growth parameters. A glass substrate instead of wafer also allows for a bifacial cell design for increased efficiency. A cost effective ~30% efficient III-V tandem solar cell in today’s market would revolutionize the solar energy industry by dramatically reducing the balance of system (BoS) costs, and thereby reduce the need for fossil fuel generated electricity. Silicon wafer technology based on polycrystalline or monocrystalline silicon could become obsolete.

Importantly, the entire patented process for the Solar-Tectic LLC III-V tandem cell can be environmentally friendly since non-toxic metals can be used to deposit the crystalline thin-film materials for both the bottom layer in the tandem configuration as well as in the top, III-V, layer.

The technology also has great promise for LED manufacturing using for example Gallium Nitride.

A “Tandem Series” of solar cell technologies has been launched by Solar-Tectic LLC, which includes a variety of different proven semiconductor photovoltaic materials for the top layer on silicon and/or germanium bottom layers. Recently patents for a tin perovskite and germanium perovskite thin-film tandem solar cell were also granted.

The ITC ruling on September 22 means that it is likely that tariffs will be imposed on crystalline silicon wafers sold in the US. These tariffs will not apply to thin-film solar cell technology, such as ST’s.

Researchers have shown that defects in the molecular structure of perovskites – a material which could revolutionise the solar cell industry – can be “healed” by exposing it to light and just the right amount of humidity.

The international team of researchers demonstrated in 2016 that defects in the crystalline structure of perovskites could be healed by exposing them to light, but the effects were temporary.

Now, an expanded team, from Cambridge, MIT, Oxford, Bath and Delft, have shown that these defects can be permanently healed, which could further accelerate the development of cheap, high-performance perovskite-based solar cells that rival the efficiency of silicon. Their results are reported in the inaugural edition of the journal Joule, published by Cell Press.

The concoction of light with water and oxygen molecules leads to substantial defect-healing in metal halide perovskite semiconductors. Credit: Dr. Matthew T. Klug

The concoction of light with water and oxygen molecules leads to substantial defect-healing in metal halide perovskite semiconductors. Credit: Dr. Matthew T. Klug

Most solar cells on the market today are silicon-based, but since they are expensive and energy-intensive to produce, researchers have been searching for alternative materials for solar cells and other photovoltaics. Perovskites are perhaps the most promising of these alternatives: they are cheap and easy to produce, and in just a few short years of development, perovskites have become almost as efficient as silicon at converting sunlight into electricity.

Despite the potential of perovskites, some limitations have hampered their efficiency and consistency. Tiny defects in the crystalline structure of perovskites, called traps, can cause electrons to get “stuck” before their energy can be harnessed. The easier that electrons can move around in a solar cell material, the more efficient that material will be at converting photons, particles of light, into electricity.

“In perovskite solar cells and LEDs, you tend to lose a lot of efficiency through defects,” said Dr Sam Stranks, who led the research while he was a Marie Curie Fellow jointly at MIT and Cambridge. “We want to know the origins of the defects so that we can eliminate them and make perovskites more efficient.”

In a 2016 paper, Stranks and his colleagues found that when perovskites were exposed to illumination, iodide ions – atoms stripped of an electron so that they carry an electric charge – migrated away from the illuminated region, and in the process swept away most of the defects in that region along with them. However, these effects, while promising, were temporary because the ions migrated back to similar positions when the light was removed.

In the new study, the team made a perovskite-based device, printed using techniques compatible with scalable roll-to-roll processes, but before the device was completed, they exposed it to light, oxygen and humidity. Perovskites often start to degrade when exposed to humidity, but the team found that when humidity levels were between 40 and 50 percent, and the exposure was limited to 30 minutes, degradation did not occur. Once the exposure was complete, the remaining layers were deposited to finish the device.

When the light was applied, electrons bound with oxygen, forming a superoxide that could very effectively bind to electron traps and prevent these traps from hindering electrons. In the accompanying presence of water, the perovskite surface also gets converted to a protective shell. The shell coating removes traps from the surfaces but also locks in the superoxide, meaning that the performance improvements in the perovskites are now long-lived.

“It’s counter-intuitive, but applying humidity and light makes the perovskite solar cells more luminescent, a property which is extremely important if you want efficient solar cells,” said Stranks, who is now based at Cambridge’s Cavendish Laboratory. “We’ve seen an increase in luminescence efficiency from one percent to 89 percent, and we think we could get it all the way to 100 percent, which means we could have no voltage loss – but there’s still a lot of work to be done.”

Samsung Electronics Co., Ltd. today announced the launch of the “Q-series,” a new line-up of LED linear modules for use in premium indoor luminaire applications where an exceptionally high level of light efficacy* is required.

The Q-series features 200 lumens per watt (lm/W) of light efficacy, which is the highest efficacy level among current LED linear modules. The new modules are the first to incorporate the LM301B, Samsung’s recently announced mid-power LED package.

This allows LED lighting fixtures using the new modules to reach more than 150lm/W, enabled through an optical efficiency level of approximately 86 percent and LED driver efficiency of about 88 percent. The Q-series’ performance levels are ideally suited to meet DLC** Premium technical standards, which require higher efficacy and lumen maintenance specifications than the DLC Standard classification.

The new Q-series modules come in one-, two- and four-foot sizes, and can be combined linearly to achieve any desired length. There are two sets of modules: Q-series modules for the North American market are UL certified, while those for the European market have CE certification.

With the addition of the premium Q-series line-up, Samsung now offers five families of LED lighting modules (Q-, H-, M-, S- and V-series) to meet most indoor LED lighting needs. The Q-series has the same form factor as Samsung’s other modules for easy retrofitting with existing LED luminaires and is now available through Samsung’s worldwide LED sales network.

Samsung’s Q-series line-up includes:

(@ tp = 40 ºC, 4000K)
Region Type Model Luminous Flux Efficacy Conditions
US

4 ft.

LT-QB22A

4,000 lm

 203 lm/W

450 mA, 43.8 V
2 ft. LT-Q562A

2,000 lm

 450 mA, 21.9 V
1 ft. LT-Q282A

1,000 lm

 450 mA, 11.0 V
Europe 2 ft. LT-Q562B 2,000 lm 180 mA, 54.8 V
1 ft. LT-Q282B 1,000 lm 180 mA, 27.4 V

ROHM has recently announced the availability of the industry’s smallest class (1608 size) of 2-color chip LEDs. In addition to their breakthrough size, the SML-D22MUW features a special design that improves reliability along with a backside electrode configuration that supports high-resolution displays.

In recent years, chip LEDs are being increasingly used for numerical displays in industrial equipment and consumer devices. Conventional numerical displays utilize a single color to indicate numbers, but there is a growing need to change the color to make it easier to recognize abnormalities. However, this typically entails utilizing two separate LEDs, which doubles the mounting area along with development costs, or opting for a standard 2-color LED that also increases board size.

In contrast, proprietary technologies and processes allowed ROHM to integrate 2 chips in the same package size as conventional single-color LEDs, making it possible to emit multiple colors in a smaller footprint. Board space is reduced by 35% over standard 1.5 x 1.3mm 2-color LEDs, contributing to thinner displays. And after taking into consideration usage conditions during reflow, countermeasures were adopted that prevents solder penetration within the resin package to ensure greater reliability.

A team of engineers has developed stretchable fuel cells that extract energy from sweat and are capable of powering electronics, such as LEDs and Bluetooth radios. The biofuel cells generate 10 times more power per surface area than any existing wearable biofuel cells. The devices could be used to power a range of wearable devices.

The epidermal biofuel cells are a major breakthrough in the field, which has been struggling with making the devices that are stretchable enough and powerful enough. Engineers from the University of California San Diego were able to achieve this breakthrough thanks to a combination of clever chemistry, advanced materials and electronic interfaces. This allowed them to build a stretchable electronic foundation by using lithography and by using screen-printing to make 3D carbon nanotube-based cathode and anode arrays.

The biofuel cells are equipped with an enzyme that oxidizes the lactic acid present in human sweat to generate current. This turns the sweat into a source of power.

Engineers report their results in the June issue of Energy & Environmental Science. In the paper, they describe how they connected the biofuel cells to a custom-made circuit board and demonstrated the device was able to power an LED while a person wearing it exercised on a stationary bike. Professor Joseph Wang, who directs the Center for Wearable Sensors at UC San Diego, led the research, in collaboration with electrical engineering professor and center co-director Patrick Mercier and nanoegnineering professor Sheng Xu, both also at the Jacobs School of Engineering UC San Diego.

The biofuel cell can stretch and flex, conforming to the human body. Credit: University of California San Diego

The biofuel cell can stretch and flex, conforming to the human body. Credit: University of California San Diego

Islands and bridges

To be compatible with wearable devices, the biofuel cell needs to be flexible and stretchable. So engineers decided to use what they call a “bridge and island” structure developed in Xu’s research group. Essentially, the cell is made up of rows of dots that are each connected by spring-shaped structures. Half of the dots make up the cell’s anode; the other half are the cathode. The spring-like structures can stretch and bend, making the cell flexible without deforming the anode and cathode.

The basis for the islands and bridges structure was manufactured via lithography and is made of gold. As a second step, researchers used screen printing to deposit layers of biofuel materials on top of the anode and cathode dots.

Increasing energy density

The researchers’ biggest challenge was increasing the biofuel cell’s energy density, meaning the amount of energy it can generate per surface area. Increasing energy density is key to increasing performance for the biofuel cells. The more energy the cells can generate, the more powerful they can be.

“We needed to figure out the best combination of materials to use and in what ratio to use them,” said Amay Bandodkar, one of the paper’s first authors, who was then a Ph.D. student in Wang’s research group. He is now a postdoctoral researcher at Northwestern University.

To increase power density, engineers screen printed a 3D carbon nanotube structure on top the anodes and cathodes. The structure allows engineers to load each anodic dot with more of the enzyme that reacts to lactic acid and silver oxide at the cathode dots. In addition, the tubes allow easier electron transfer, which improves biofuel cell performance.

Testing applications

The biofuel cell was connected to a custom-made circuit board manufactured in Mercier’s research group. The board is a DC/DC converter that evens out the power generated by the fuel cells, which fluctuates with the amount of sweat produced by a user, and turns it into constant power with a constant voltage.

Researchers equipped four subjects with the biofuel cell-board combination and had them exercise on a stationary bike. The subjects were able to power a blue LED for about four minutes.

Next steps

Future work is needed in two areas. First, the silver oxide used at the cathode is light sensitive and degrades over time. In the long run, researchers will need to find a more stable material.

Also, the concentration of lactic acid in a person’s sweat gets diluted over time. That is why subjects were able to light up an LED for only four minutes while biking. The team is exploring a way to store the energy produced while the concentration of lactate is high enough and then release it gradually.

Standard light-emitting diodes (LEDs) used for home lighting can now transmit data more rapidly between electronic devices, thanks to new research from A*STAR.

Wireless visible light communication—also known as Li-Fi—relies on data signals encoded in incredibly brief pulses of light, far too quick for the eye to see. By supplementing congested Wi-Fi networks, Li-Fi could increase the capacity and speed of data transmission in offices, homes and public spaces. However, white LEDs typically use a phosphor coating to create a natural-looking white light, and the time it takes for the phosphor’s glow to fade away limits how quickly the LED can transmit data.

Previous solutions typically required installing new types of white LEDs. Instead, Ee Jin Teo of the A*STAR Institute of Materials Research and Engineering, and colleagues, have developed a Li-Fi receiver that overcomes these problems. Rather than using a conventional silicon photodiode to detect transmissions, they found that an indium gallium nitride (InGaN) LED is an effective data receiver.

Crucially, the team’s InGaN LEDs can detect only the ‘fast’ blue component of the phosphor’s white light, which fades in only one nanosecond, and not the ‘slow’ yellow component which takes more than 50 nanoseconds to fade away.

The researchers also gave their InGaN LED a textured surface, so that every square centimeter was covered with one billion V-shaped pits (see image), roughly 150 nanometers deep. These V-pits scatter incoming light, allowing the LED’s active layers to absorb more than twice as much blue light as an LED with a smooth surface.

Tests with a white LED showed that the InGaN LED with V-pits was a much better receiver than a standard silicon photodetector. “Using a silicon photodetector, the white LED can reach a switching speed of five megahertz—this typically means a data transmission rate of up to 100 megabits per second,” says Teo. “With our InGaN LED as a detector, this switching speed can be increased by four times, enabling faster data transmission rates from white LEDs.”

She notes, however, that since the receiver is only picking up part of the white LED’s light, it may reduce the range over which data can be transmitted.

“The next stage of our research,” she adds, “is to implement this concept into a dongle where the same LED can be used for transmission as well as detection of data.”

Energy loss due to scattering from material defects is known to set limits on the performance of nearly all technologies that we employ for communications, timing, and navigation. In micro-mechanical gyroscopes and accelerometers, such as those commonly found in cellphones today, microstructural disorder impacts measurement drift and overall accuracy of the sensor, analogous to how a dirty violin string might impact one’s enjoyment of beautiful music. In optical fiber communication systems, scattering from material defects can reduce data fidelity over long distances thereby reducing achievable bandwidth. Since defect-free materials cannot be obtained, how can we possibly improve on the fundamental technological limits imposed by disorder?

A research collaboration between the University of Illinois at Urbana-Champaign, the National Institute of Standards and Technology, and the University of Maryland has revealed a new technique by which scattering of sound waves from disorder in a material can be suppressed on demand. All of this, can be simply achieved by illuminating with the appropriate color of laser light. The result, which is published in Nature Communications, could have a wide-ranging impact on sensors and communication systems.

This is a microscope image of a silica glass resonator and optical fiber waveguide. Light and sound circulating in this type of resonator are shown to exhibit chiral effects in this study. (Credit: Gaurav Bahl, University of Illinois Department of Mechanical Science and Engineering)

This is a microscope image of a silica glass resonator and optical fiber waveguide. Light and sound circulating in this type of resonator are shown to exhibit chiral effects in this study. (Credit: Gaurav Bahl, University of Illinois Department of Mechanical Science and Engineering)

Gaurav Bahl, an assistant professor of mechanical science and engineering, and his research team have been studying the interaction of light with sound in solid state micro-resonators. This new result is the culmination of a series of experiments pursued by his team over the past several years, and a new scientific question posed in the right place.

“Resonators can be thought of as echo chambers for sound and light, and can be as simple as micro-spherical balls of glass like those we used in our study,” Bahl explained. “Our research community has long understood that light can be used to create and amplify sound waves in resonators through a variety of optical forces. The resonant echoes help to increase the interaction time between sound, light, and material disorder, making these subtle effects much easier to observe and control. Since interactions within resonators are fundamentally no different from those taking place in any other system, these can be a really compact platform for exploring the underlying physics.”

The key to suppressing scattering from disorder is to induce a mismatch in the propagation between the original and scattered directions. This idea is similar to how an electric current prefers to flow along the path of least resistance, or how water prefers to flow through a wider pipe rather than a constricted one. To suppress back-scattering of forward-moving sound waves, one must create a large acoustic impedance in the backward direction. This asymmetry for forward and backward propagating waves is termed as chirality of the medium. Most solid-state systems do not have chiral properties, but these properties can be induced through magnetic fields or through space-time variation of the medium.

“A few years ago, we discovered that chirality can be induced for light using an opto-mechanical phenomenon, in which light couples with propagating sound waves and renders the medium transparent. Our experiments at that time showed that the induced optical transparency only allows light to move unidirectionally, that is, it creates a preferentially low optical impedance in one direction,” Bahl said. “It is then that we met our collaborator Jacob Taylor, a physicist at NIST, who asked us a simple question. What happens to the sound waves in such a system?”

“Our theoretical modeling predicted that having a chiral system for sound propagation could suppress any back-scattering that may have been induced by disorder,” explained Taylor. “This concept arose from work we’ve been doing in the past few years investigating topological protection for light, where chiral propagation is a key feature for improving the performance of devices. Initially the plan with Bahl’s team was just to show a difference between the forward and backward propagating sound waves, using a cooling effect created by light. But the system surprised us with an even stronger practical effect than expected.”

That simple question launched a new multi-year research effort in a direction that has not been explored previously. Working in close collaboration, the team discovered that Brillouin light scattering, a specific kind of opto-mechanical interaction, could also induce chirality for sound waves. Between the experimental tools in Bahl’s lab, and the theoretical advancements in Taylor’s lab, the pieces of the puzzle were already in place.

“We experimentally prepared a chiral optomechanical system by circulating a laser field in the clockwise direction in a silica glass resonator. The laser wavelength, or color, was specially arranged to induce optical damping of only clockwise sound waves. This created a large acoustic impedance mismatch between clockwise and counter-clockwise directions of propagation,” explained Seunghwi Kim, first author of the study. “Sound waves that were propagating the clockwise direction experienced very high losses due to the opto-mechanical cooling effect. Sound waves moving in the counter-clockwise direction could move freely. Surprisingly, we saw a huge reduction of scattering loss for counter-clockwise sound waves, since those waves could no longer scatter into the clockwise direction! In other words, even though disorder was present in the resonator, its action was suppressed.”

Just as sound is the primary method of voice communication between humans, electromagnetic waves like radio and light are the primary technology used for global communications. What could this discovery mean for the communications industry? Disorder and material defects are unavoidable optical fiber systems, resulting in lower data fidelity, bit errors, and bandwidth limitations. The team believes that technologies based on this discovery could be leveraged to circumvent the impact of unavoidable material defects in such systems.

“We’ve seen already that many sensors, such as those found in your phone or in your car, can be limited by intrinsic defects in the materials,” added Taylor. “The approach introduced here provides a simple means of circumventing those challenges, and may even help us approach the limits set by quantum mechanics, rather than our own engineering challenges.”

Practical applications of this result may not be too many years off. Reduction of mechanical losses could also directly improve mechanics-based inertial navigation sensors that we use today. Examples that we encounter in daily life are accelerometers and gyroscopes, without which our mobile phones would be a lot less capable, and our cars and airplanes a lot less safe.

A hypoallergenic electronic sensor can be worn on the skin continuously for a week without discomfort, and is so light and thin that users forget they even have it on, says a Japanese group of scientists. The elastic electrode constructed of breathable nanoscale meshes holds promise for the development of noninvasive e-skin devices that can monitor a person’s health continuously over a long period.

Wearable electronics that monitor heart rate and other vital health signals have made headway in recent years, with next-generation gadgets employing lightweight, highly elastic materials attached directly onto the skin for more sensitive, precise measurements. However, although the ultrathin films and rubber sheets used in these devices adhere and conform well to the skin, their lack of breathability is deemed unsafe for long-term use: dermatological tests show the fine, stretchable materials prevent sweating and block airflow around the skin, causing irritation and inflammation, which ultimately could lead to lasting physiological and psychological effects.

“We learned that devices that can be worn for a week or longer for continuous monitoring were needed for practical use in medical and sports applications,” says Professor Takao Someya at the University of Tokyo’s Graduate School of Engineering whose research group had previously developed an on-skin patch that measured oxygen in blood.

In the current research, the group developed an electrode constructed from nanoscale meshes containing a water-soluble polymer, polyvinyl alcohol (PVA), and a gold layer–materials considered safe and biologically compatible with the body. The device can be applied by spraying a tiny amount of water, which dissolves the PVA nanofibers and allows it to stick easily to the skin–it conformed seamlessly to curvilinear surfaces of human skin, such as sweat pores and the ridges of an index finger’s fingerprint pattern.

The researchers next conducted a skin patch test on 20 subjects and detected no inflammation on the participants’ skin after they had worn the device for a week. The group also evaluated the permeability, with water vapor, of the nanomesh conductor–along with those of other substrates like ultrathin plastic foil and a thin rubber sheet–and found that its porous mesh structure exhibited superior gas permeability compared to that of the other materials.

Furthermore, the scientists proved the device’s mechanical durability through repeated bending and stretching, exceeding 10,000 times, of a conductor attached on the forefinger; they also established its reliability as an electrode for electromyogram recordings when its readings of the electrical activity of muscles were comparable to those obtained through conventional gel electrodes.

“It will become possible to monitor patients’ vital signs without causing any stress or discomfort,” says Someya about the future implications of the team’s research. In addition to nursing care and medical applications, the new device promises to enable continuous, precise monitoring of athletes’ physiological signals and bodily motion without impeding their training or performance.

The electric current from a flexible battery placed near the knuckle flows through the conductor and powers the LED just below the fingernail. Credit: 2017 Someya Laboratory.

The electric current from a flexible battery placed near the knuckle flows through the conductor and powers the LED just below the fingernail. Credit: 2017 Someya Laboratory.

Javier Vela, scientist at the U.S. Department of Energy’s Ames Laboratory, believes improvements in computer processors, TV displays and solar cells will come from scientific advancements in the synthesis of low-dimensional nanomaterials.

Ames Laboratory scientists are known for their expertise in the synthesis and manufacturing of materials of different types, according to Vela, who is also an Iowa State University associate professor of chemistry. In many instances, those new materials are made in bulk form, which means micrometers to centimeters in size. Vela’s group is working with tiny, nanometer, or one billionth of a meter sized, nanocrystals.

“We’re trying to find out what happens with materials when we go to lower particle sizes, will the materials be enhanced or negatively impacted, or will we find properties that weren’t expected,” Vela said. “Our goal is to broaden the science of low-dimensional nanomaterials.” In an invited paper published in Chemistry of Materials entitled, “Synthetic Development of Low Dimensional Materials”, Vela and coauthors Long Men, Miles White, Himashi Andaraarachchi, and Bryan Rosales discussed highlights of some of their most recent work on the synthesis of low dimensional materials.

One of those topics was advancements in the synthesis of germanium-based core-shell nanocrystals. Vela says industry is very interested in semiconducting nanocrystal-based technologies for applications such as solar cells.

Small particle size can affect many things from transport properties (how well a nanocrystal conducts heat and electricity) to optical properties (how strong it interacts with light, absorbs light and emits light). This is especially true in photovoltaic solar cells “Let’s say you’re using a semiconductor material to make a solar device, there’s often different performance when solar cells are made from bulk materials as opposed to when they are made with nanomaterials. Nanomaterials interact with light differently; they absorb it better. That’s one way you can manipulate devices and fine tune their performance or power conversion efficiency,” said Vela.

Beyond solar cells, Vela says there’s tremendous interest in using nanocrystals in quantum dot television and computer displays, optical devices like LEDs (light-emitting diodes), biological imaging, and telecommunications.

He says there are many challenges in this area because depending upon the quality of the nanocrystals used, you can see different emission properties, which can affect the purity of light. “Ultimately the size of the nanocrystals being used can make a huge difference in the cleanliness or crispness of colors in TV and computer displays,” said Vela. “Television and computer technology is a multibillion dollar business worldwide, so you can see the potential value our understanding of properties of nanocrystals could bring to these technologies.”

In the paper, Vela’s group also discussed advancements made in the study of synthesis and spectroscopic characterization of organolead halide perovskites, which Vela says are some of the most promising semiconductors for solar cells because of their low cost and easier processability. He adds photovoltaics made of these materials now reach power conversion efficiencies of greater than 22 percent. Vela’s research in this area has focused on mixed-halide perovskites. He says his group has discovered these materials exhibit interesting chemical and photo physical properties that people hadn’t realized before, and now they are trying to better understand the correlation between the structure and chemical composition of perovskites and how they behave in solar cells. “One of our goals is to use what we’ve learned to help lower the cost of solar cells and produce them more reliably and readily,” Vela said.

In addition, Vela’s group is studying how to replace lead in traditional organolead halide perovskites with something less toxic, like germanium. “In principle, this is an area that should be much better known, but it’s not,” said Vela. “When we’ve been able to substitute germanium for lead, we have been able to produce a lighter perovskite, which he says could positively impact the automotive industry, for example.

“This could have great implications for transportation applications where you don’t want a lot of lead because it’s so heavy,” said Vela. Going forward Vela says his group’s focus will be on advancing the science in low-dimensional materials.

“We’re not working with well-known materials, but the newest; the most recently discovered,” Vela said. “And every time we can advance the science we’re one step closer to opportunities for more commercialization, more production, more manufacturing and more jobs in the U.S.”

Osram Opto Semiconductors today presented the latest generation of surface-mountable LED, the Topled E1608, with a package smaller than its predecessor models by a factor of 20. Despite this considerable miniaturization, the low-power LED is bright, reliable and robust, offering greater options and design flexibility, particularly for car interior applications.

ThinGaN, thin film and Sapphire – the new Topled E1608 LEDs from Osram Opto Semiconductors are based on the latest chip technologies. In combination with the latest high-efficiency converters, the low-power LEDs produce outstanding performance values. At a normal operating current of 20 mA, the new Topleds are 3.6 times brighter than preceding models. The converted pure green version, for example, achieves the impressive and unprecedented value of 780 mcd at 10 mA. For the package, Osram uses tried and tested pre-mold technology, but reduced in size compared to the previous version. The E1608 in the name refers to the more compact package dimensions of 1.6 mm x 0.8 mm compared to the standard Topled measuring 3.2 mm x 2.8 mm. At 0.6 mm, the E1608 height is also considerably less than the previous height of 1.9 mm.

Due to the new package dimensions, the E1608 can now be used for more compact customer systems.

“The new Topled E1608 LEDs are some of the smallest LEDs in their class, offering reliability, a wide selection of colors and impressive performance values,” said Michael Godwin, Director, World Wide Interior Automotive Products, Osram Opto Semiconductors. “In addition, they are suitable for all customer requirements – whether the application is toward the top or bottom of the brightness range. We anticipate they will become firmly established in the market and may eventually define a new industry standard. These robust LEDs are suitable particularly for the automotive sector for applications such as displays, ambient lighting and backlighting of switches and instruments.”

Osram’s next-gen Topled will be available in numerous colors – from yellow and orange to super red, white, pure green and true green as part of the current market launch, expected to be the first of an entire series throughout the remainder of 2017.

OSRAM-TOPLED-20E-product