Category Archives: LED Manufacturing

Harnessing the power of the sun and creating light-harvesting or light-sensing devices requires a material that both absorbs light efficiently and converts the energy to highly mobile electrical current. Finding the ideal mix of properties in a single material is a challenge, so scientists have been experimenting with ways to combine different materials to create “hybrids” with enhanced features.

In two just-published papers, scientists from the U.S. Department of Energy’s Brookhaven National Laboratory, Stony Brook University, and the University of Nebraska describe one such approach that combines the excellent light-harvesting properties of quantum dots with the tunable electrical conductivity of a layered tin disulfide semiconductor. The hybrid material exhibited enhanced light-harvesting properties through the absorption of light by the quantum dots and their energy transfer to tin disulfide, both in laboratory tests and when incorporated into electronic devices. The research paves the way for using these materials in optoelectronic applications such as energy-harvesting photovoltaics, light sensors, and light emitting diodes (LEDs).

According to Mircea Cotlet, the physical chemist who led this work at Brookhaven Lab’s Center for Functional Nanomaterials (CFN), a DOE Office of Science User Facility, “Two-dimensional metal dichalcogenides like tin disulfide have some promising properties for solar energy conversion and photodetector applications, including a high surface-to-volume aspect ratio. But no semiconducting material has it all. These materials are very thin and they are poor light absorbers. So we were trying to mix them with other nanomaterials like light-absorbing quantum dots to improve their performance through energy transfer.”

One paper, just published in the journal ACS Nano, describes a fundamental study of the hybrid quantum dot/tin disulfide material by itself. The work analyzes how light excites the quantum dots (made of a cadmium selenide core surrounded by a zinc sulfide shell), which then transfer the absorbed energy to layers of nearby tin disulfide.

“We have come up with an interesting approach to discriminate energy transfer from charge transfer, two common types of interactions promoted by light in such hybrids,” said Prahlad Routh, a graduate student from Stony Brook University working with Cotlet and co-first author of the ACS Nano paper. “We do this using single nanocrystal spectroscopy to look at how individual quantum dots blink when interacting with sheet-like tin disulfide. This straightforward method can assess whether components in such semiconducting hybrids interact either by energy or by charge transfer.”

The researchers found that the rate for non-radiative energy transfer from individual quantum dots to tin disulfide increases with an increasing number of tin disulfide layers. But performance in laboratory tests isn’t enough to prove the merits of potential new materials. So the scientists incorporated the hybrid material into an electronic device, a photo-field-effect-transistor, a type of photon detector commonly used for light sensing applications.

As described in a paper published online March 24 in Applied Physics Letters, the hybrid material dramatically enhanced the performance of the photo-field-effect transistors-resulting in a photocurrent response (conversion of light to electric current) that was 500 percent better than transistors made with the tin disulfide material alone.

“This kind of energy transfer is a key process that enables photosynthesis in nature,” said Chang-Yong Nam, a materials scientist at Center for Functional Nanomaterials and co-corresponding author of the APL paper. “Researchers have been trying to emulate this principle in light-harvesting electrical devices, but it has been difficult particularly for new material systems such as the tin disulfide we studied. Our device demonstrates the performance benefits realized by using both energy transfer processes and new low-dimensional materials.”

Cotlet concludes, “The idea of ‘doping’ two-dimensional layered materials with quantum dots to enhance their light absorbing properties shows promise for designing better solar cells and photodetectors.”

Researchers from the University of Illinois at Urbana-Champaign have demonstrated a new approach to modifying the light absorption and stretchability of atomically thin two-dimensional (2D) materials by surface topographic engineering using only mechanical strain. The highly flexible system has future potential for wearable technology and integrated biomedical optical sensing technology when combined with flexible light-emitting diodes.

“Increasing graphene’s low light absorption in visible range is an important prerequisite for its broad potential applications in photonics and sensing,” explained SungWoo Nam, an assistant professor of mechanical science and engineering at Illinois. “This is the very first stretchable photodetector based exclusively on graphene with strain-tunable photoresponsivity and wavelength selectivity.”

Graphene–an atomically thin layer of hexagonally bonded carbon atoms–has been extensively investigated in advanced photodetectors for its broadband absorption, high carrier mobility, and mechanical flexibility. Due to graphene’s low optical absorptivity, graphene photodetector research so far has focused on hybrid systems to increase photoabsorption. However, such hybrid systems require a complicated integration process, and lead to reduced carrier mobility due to the heterogeneous interfaces.

According to Nam, the key element enabling increased absorption and stretchability requires engineering the two-dimensional material into three-dimensional (3D) “crumpled structures,” increasing the graphene’s areal density. The continuously undulating 3D surface induces an areal density increase to yield higher optical absorption per unit area, thereby improving photoresponsivity. Crumple density, height, and pitch are modulated by applied strain and the crumpling is fully reversible during cyclical stretching and release, introducing a new capability of strain-tunable photoabsorption enhancement and allowing for a highly responsive photodetector based on a single graphene layer.

“We achieved more than an order-of-magnitude enhancement of the optical extinction via the buckled 3D structure, which led to an approximately 400% enhancement in photoresponsivity,” stated Pilgyu Kang, and first author of the paper, “Crumpled Graphene Photodetector with Enhanced, Strain-tunable and Wavelength-selective Photoresponsivity,” appearing in the journal, Advanced Materials. “The new strain-tunable photoresponsivity resulted in a 100% modulation in photoresponsivity with a 200% applied strain. By integrating colloidal photonic crystal–a strain-tunable optomechanical filter–with the stretchable graphene photodetector, we also demonstrated a unique strain-tunable wavelength selectivity.”

“This work demonstrates a robust approach for stretchable and flexible graphene photodetector devices,” Nam added. “We are the first to report a stretchable photodetector with stretching capability to 200% of its original length and no limit on detection wavelength. Furthermore, our approach to enhancing photoabsorption by crumpled structures can be applied not only to graphene, but also to other emerging 2D materials.”

Becoming crystal clear


April 6, 2016

Using state-of-the-art theoretical methods, UCSB researchers have identified a specific type of defect in the atomic structure of a light-emitting diode (LED) that results in less efficient performance. The characterization of these point defects could result in the fabrication of even more efficient, longer lasting LED lighting.

“Techniques are available to assess whether such defects are present in the LED materials and they can be used to improve the quality of the material,” said materials professor Chris Van de Walle, whose research group carried out the work.

In the world of high-efficiency solid-state lighting, not all LEDs are alike. As the technology is utilized in a more diverse array of applications — including search and rescue, water purification and safety illumination, in addition to their many residential, industrial and decorative uses — reliability and efficiency are top priorities. Performance, in turn, is heavily reliant on the quality of the semiconductor material at the atomic level.

“In an LED, electrons are injected from one side, holes from the other,” explained Van de Walle. As they travel across the crystal lattice of the semiconductor — in this case gallium-nitride-based material — the meeting of electrons and holes (the absence of electrons) is what is responsible for the light that is emitted by the diode: As electron meets hole, it transitions to a lower state of energy, releasing a photon along the way.

Occasionally, however, the charge carriers meet and do not emit light, resulting in the so-called Shockley-Read-Hall (SRH) recombination. According to the researchers, the charge carriers are captured at defects in the lattice where they combine, but without emitting light.

The defects identified involve complexes of gallium vacancies with oxygen and hydrogen. “These defects had been previously observed in nitride semiconductors, but until now, their detrimental effects were not understood,” explained lead author Cyrus Dreyer, who performed many of the calculations on the paper.

“It was the combination of the intuition that we have developed over many years of studying point defects with these new theoretical capabilities that enabled this breakthrough,” said Van de Walle, who credits co-author Audrius Alkauskas with the development of a theoretical formalism necessary to calculate the rate at which defects capture electrons and holes.

The method lends itself to future work identifying other defects and mechanisms by which SRH recombination occurs, said Van de Walle.

“These gallium vacancy complexes are surely not the only defects that are detrimental,” he said. “Now that we have the methodology in place, we are actively investigating other potential defects to assess their impact on nonradiative recombination.”

Samsung Electronics Co. and Daintree Networks said they are collaborating on joint solutions involving Samsung’s smart lighting module (SLM).

According to a release, Samsung’s SLM, which will be integrated with LED luminaires from lighting OEMs, enables greater intelligence through device-level processing, as well as enhanced connectivity through multiple embedded communications technologies, including the open standard ZigBee protocol. Combining Samsung’s SLM technology with the Daintree Networks ControlScope networked wireless control solution makes new Internet of Things (IoT) applications possible for smart buildings.

Dr. Jacob Tarn, Executive Vice President, LED Business Team, Samsung Electronics, said, “Samsung’s SLM technology will make all devices connected to it, from LED luminaires to sensors to future control products, even smarter. Because SLM is the key for a wide variety of smart lighting applications, our customers can achieve fast time-to-market and their luminaires can be optimized for many different smart lighting environments. By partnering with Daintree Networks, with their ControlScope solution, we will support traditional lighting control as well as enable new sensor-driven applications. For example, by connecting third-party occupancy sensors to our SLM technology, ControlScope customers will be able to more accurately monitor occupant patterns that can improve business operations and enhance security in retail environments.”

“Our partnership with Samsung reinforces our commitment to provide open wireless networking solutions to enable the Enterprise Internet of ThingsTM (E-IoTTM),” said Derek Proudian, Chairman and Chief Executive Officer of Daintree Networks. “The unique architecture found in Samsung’s SLM is a great match for the advanced technology in ControlScope and further demonstrates connected LED lighting as the natural infrastructure for smart buildings across retail, office and industrial environments. With an expanding array of open standard control devices and open software innovation, Daintree is accelerating the development of high-value business outcomes for our enterprise customers. We are excited to collaborate with Samsung to advance our industry.”

ControlScope is an open standards-based mesh networking control solution and enterprise IoT platform. Daintree Networks provides the in-building wireless network communications and cloud-based intelligent control software, and customers are free to choose from a variety of third-party control devices including sensors, fixtures, programmable thermostats.

The industrial semiconductor market will post an 8 percent compound annual growth rate (CAGR), as revenue rises from $43.5 billion in 2014 to $59.5 billion in 2019. Increased capital spending and continued economic growth, especially in the United States, will spur demand and industrial semiconductor sales growth, according to IHS Inc. (NYSE: IHS), a global source of critical information and insight. Commercial aircraft, LED lighting, digital video surveillance, climate control, traction and medical devices are driving most of the global demand for industrial semiconductors.

The greatest semiconductor growth will come from LEDs, which is expected to reach $14.5 billion in 2019, stemming from the global LED lighting boom. Discrete power transistors, thyristors, rectifiers and power diodes are expected to hit $7.8 billion in revenue, due to the policy shift toward energy efficiency in the factory automation market.

According to the IHS Industrial Semiconductors Intelligence Service, analog application-specific integrated circuits (ICs) can expect strong growth through 2019, reaching $4.7 billion in industrial markets, especially in factory automation, power and energy, and lighting. Growth will primarily come from various power management product portfolio offerings and device integration from Texas Instruments (TI), Analog Devices (ADI), NXP and other leading semiconductor firms. Microcontrollers (MCUs) are also expected to experience robust growth in the long term, growing from $4.4 billion to $6.3 billion, thanks to advances in power efficiency and integration features.

Total industrial original equipment manufacturing (OEM) factory revenue is forecast to grow at a CAGR of 5 percent, reaching $670 billion in 2019. Industrial OEM factory revenues specifically grew 6 percent in 2015 driven by increased sales in building and home-control, and military and civil aerospace sectors. High-growth categories include LED lighting, climate control, digital video surveillance products and commercial aircraft.

With its comparatively strong global economy, the United States accounted for 30 percent of all semiconductors used in industrial applications in 2015. China was the second largest industrial chip buyer, purchasing about 16 percent of all industrial semiconductors last year.

“Robust economic growth and increased capital spending in the United States is good news for industrial semiconductor suppliers, because they have the world’s largest industrial equipment makers, including General Electric, United Technologies and Boeing,” said Robbie Galoso, associate director, industrial semiconductors, IHS Technology. “Strong industrial equipment demand will further boost sales of optical semiconductors, analog chips and discretes, which are the three largest industrial semiconductor product segments.”

Soraa, a developer of GaN on GaN LED technology, today announces its support for advances in color science and the new TM-30 method released by the Illuminating Engineering Society (IES). TM-30 uses an optimized calculation method to preclude the errors found in the color-rendering index (CRI), the current industry standard.

As a leader in developing products with superior light quality, Soraa is a strong supporter of advances in color science. Illuminating the way, Soraa Chief Scientist Aurelien David served as a lead technical contributor for the new TM-30 method.

“IES’s TM-30 method offers significant progress over the CRI,” said David. “For customers, TM-30 will provide better insight in to how the colors of a light source compare to colors under natural light. And for manufacturers, the information found under TM-30—combined with other aspects of color science—will be key for developing better products and optimizing the trade-off between color rendition and other criteria of light quality.”

The TM-30 test was developed to provide a more accurate indication of the color rendition of an object by comparing the color of the object under a test source (a LED lamp, for example) to those under a reference illuminant (a standard emitter such as idealized sunlight or filament bulb, depending on the CCT).  By doing so, the test will indicate if the colors under the test source are different from natural colors—providing a more precise indication of color fidelity.

TM-30 distinguishes itself from the CRI test in two significant areas. First, it uses state-of-the-art color science to test a light source’s color rendition of more color samples, which will preclude the inaccurate predictions of rendering seen with the CRI—in particular for narrow-band sources. Second, it provides users with more information: the color fidelity index Rf is now complemented by a color gamut index Rg and by a color vector graphic, which further characterize the appearance of colors.

Soraa has posted more information about TM-30 on its website: www.soraa.com.

With just a tiny tweak, researchers at Kyushu University greatly increased the device lifetime of organic light-emitting diodes (OLEDs) that use a recently developed class of molecules to convert electricity into light with the potential for increased efficiency at a lower cost in future displays and lighting.

Using the OLED structure in this schematic, researchers were able to delay the degradation in brightness of an OLED with the TADF emitter 4CzIPN by eight to sixteen times. Credit: Daniel Ping-Kuen Tsang and William John Potscavage Jr.

Using the OLED structure in this schematic, researchers were able to delay the degradation in brightness of an OLED with the TADF emitter 4CzIPN by eight to sixteen times. Credit: Daniel Ping-Kuen Tsang and William John Potscavage Jr.

The easily implemented modifications can also potentially increase the lifetime of OLEDs currently used in smartphone displays and large-screen televisions.

Typical OLEDs consist of multiple layers of organic films with various functions. At the core of an OLED is an organic molecule that emits light when a negatively charged electron and a positively charged hole, which can be thought of as a missing electron, meet on the molecule.

Until recently, the light-emitting molecules were either fluorescent materials, which can be low cost but can only use about 25% of electrical charges, or phosphorescent materials, which can harvest 100% of charges but include an expensive metal such as platinum or iridium.

Researchers at Kyushu University’s Center for Organic Photonic and Electronics Research (OPERA) changed this in 2012 with the demonstration of efficient emitters based on a process called thermally activated delayed fluorescence (TADF).

Through clever molecular design, these TADF materials can convert nearly all of the electrical charges to light without the expensive metal used in phosphorescent materials, making both high efficiency and low cost possible.

However, OLEDs under constant operation degrade and become dimmer over time regardless of the emitting material.

Devices that degrade slowly are key for practical applications, and concerns remained that the lifetime of early TADF devices was still on the short side.

But with the leap in lifetime reported in a paper published online March 1, 2016, in Scientific Reports, many of those concerns can now be put to rest.

“While our initial TADF devices lost 5% of their brightness after only 85 hours,” said postdoctoral researcher Daniel Tsang, lead author on the study, “we have now extended that more than eight times just by making a simple modification to the device structure.”

The newly developed modification was to put two extremely thin (1-3 nm) layers of the lithium-containing molecule Liq on each side of the hole blocking layer, which brings electrons to the TADF material, the green emitter 4CzIPN in this case, while preventing holes from exiting the device before contributing to emission.

The devices will last even longer in practical applications because the tests are performed at extreme brightnesses to accelerate the degradation.

Applying additional optimizations that have been previously reported, the 5% drop was further delayed to longer than 1,300 hours, over 16 times that of the initial devices.

“What we are finding is that the TADF materials themselves can be very stable, making them really promising for future displays and lighting,” said Professor Chihaya Adachi, director of OPERA.

The benefits of the Liq layers are not limited to TADF-based OLEDs as the researchers also found an improvement using a similar device structure with a phosphorescent emitter.

Though still trying to completely unravel the degradation mechanism, the researchers found that devices with the Liq layers contain a much lower number of traps, a type of defect that can capture and hold a charge, preventing it from moving freely in the device.

These defects were observed by measuring tiny electrical currents created when charges that were frozen in the traps at extremely cold temperatures escape by receiving a jolt of thermal energy as the device is heated, a process called thermally stimulated current.

Having charges stuck in these traps may increase the chance for interactions with other charges and electrical excitations that can destroy the molecules and lead to degradation.

One of the next major challenges for TADF is stable and efficient blue emitting materials, which are necessary for full color displays and are also still difficult using phosphorescence.

“With the continued development of new materials and device structures,” said Prof. Adachi, “we think that TADF has the potential to solve the challenge of efficient and stable blue emission.”

Demonstrating a strategy that could form the basis for a new class of electronic devices with uniquely tunable properties, researchers at Kyushu University were able to widely vary the emission color and efficiency of organic light-emitting diodes based on exciplexes simply by changing the distance between key molecules in the devices by a few nanometers.

This new way to control electrical properties by slightly changing the device thickness instead of the materials could lead to new kinds of organic electronic devices with switching behavior or light emission that reacts to external factors.

Organic electronic devices such as OLEDs and organic solar cells use thin films of organic molecules for the electrically active materials, making flexible and low-cost devices possible.

A key factor determining the properties of organic devices is the behavior of packets of electrical energy called excitons. An exciton consists of a negative electron attracted to a positive hole, which can be thought of as a missing electron.

In OLEDs, the energy in these excitons is released as light when the electron loses energy and fills the vacancy of the hole. Varying the exciton energy, for example, will change the emission color.

However, excitons are commonly localized on a single organic molecule and tightly bound with binding energies of about 0.5 eV. Thus, entirely new molecules must usually be designed and synthesized to obtain different properties from these Frenkel-type excitons, such as red, green, or blue emission for displays.

Researchers at Kyushu University’s Center for Organic Photonics and Electronics Research (OPERA) instead focused on a different type of exciton called an exciplex, which is formed by a hole and electron located on two different molecules instead of the same molecule.

By manipulating the molecular distance between the electron-donating molecule (donor) and the electron-accepting molecule (acceptor) that carry the exciplex’s hole and electron, respectively, the researchers could modify the properties of these weakly bound excitons.

“What we did is similar to placing sheets of paper between a magnet and a refrigerator,” said Associate Professor Hajime Nakanotani, lead author of the paper reporting these results published online February 26, 2016, in the journal Science Advances.

“By increasing the thickness of an extremely thin layer of organic molecules inserted as a spacer between the donor and acceptor, we could reduce the attraction between the hole and electron in the exciplex and thereby greatly influence the exciplex’s energy, lifetime, and emission color and efficiency.”

Indeed, the changes can be large: by inserting a spacer layer with a thickness of only 5 nm between a donor layer and an acceptor layer in an OLED, the emission color shifted from orange to yellowish green and the light emission efficiency increased 700%.

For this to work, the organic molecule used for the spacer layer must have an excitation energy higher than those of the donor and acceptor, but such materials are already widely available.

While the molecular distance is currently determined by the thickness of the vacuum-deposited spacer layer, the researchers are now looking into other ways to control the distance.

“This gives us a powerful way to greatly vary device properties without redesigning or changing any of the materials,” said Professor Chihaya Adachi, director of OPERA. “In the future, we envision new types of exciton-based devices that respond to external forces like pressure to control the distance and electrical behavior.”

In addition, the researchers found that the exciplexes were still formed when the spacer was 10 nm thick, which is long on a molecular scale.

“This is some of the first evidence that electrons and holes could still interact like this across such a long distance,” commented Professor Adachi, “so this structure may also be a useful tool for studying and understanding the physics of excitons to design better OLEDs and organic solar cells in the future.”

“From both scientific and applications standpoints, we are excited to see where this new path for exciton engineering takes us and hope to establish a new category of exciton-based electronics.”

Researchers from the Moscow Institute of Physics and Technology (MIPT) have for the first time experimentally demonstrated that copper nanophotonic components can operate successfully in photonic devices – it was previously believed that only gold and silver components have the required properties for this. Copper components are not only just as good as components based on noble metals, but, unlike them, they can easily be implemented in integrated circuits using industry-standard fabrication processes.

“This is a kind of revolution – using copper will solve one of the main problems in nanophotonics,” say the authors of the paper. The results have been published in the scientific journal Nano Letters.

The discovery, which is revolutionary for photonics and the computers of the future, was made by researchers from the Laboratory of Nanooptics and Plasmonics at MIPT’s Centre of Nanoscale Optoelectronics. They have succeeded, for the first time, in producing copper nanophotonic components, whose characteristics are just as good as that of gold components. It is interesting to note that the scientists fabricated the copper components using the process compatible with the industry-standard manufacturing technologies that are used today to produce modern integrated circuits. This means that in the very near future copper nanophotonic components will form a basis for the development of energy-efficient light sources, ultra-sensitive sensors, as well as high-performance optoelectronic processors with several thousand cores.

The discovery was made under what is known as nanophotonics – a branch of research which aims, among other things, to replace existing components in data processing devices with more modern components by using photons instead of electrons. However, while the main component in modern electronics, the transistor, can be scaled down in size to a few nanometres, the diffraction of light limits the minimum dimensions of photonic components to the size of about the light wavelength (~1 micrometre). Despite the fundamental nature of this so-called diffraction limit, one can overcome it by using metal-dielectric structures to create truly nanoscale photonic components. Firstly, most metals show a negative permittivity at optical frequencies, and light cannot propagate through them, penetrating to a depth of only 25 nanometres. Secondly, light may be converted into surface plasmon polaritons, surface waves propagating along the surface of a metal. This makes it possible to switch from conventional 3D photonics to 2D surface plasmon photonics, which is known as plasmonics. This gives a possibility to control light at the scale of the order of 100 nanometres, i.e. far beyond the diffraction limit.

It was previously believed that only two metals – gold and silver – could be used to build efficient nanophotonic metal-dielectric nanostructures and it was also thought that all other metals could not be an alternative to these two materials, since they exhibit strong absorption. However, in practice, creating components using gold and silver is not possible because both metals, as they are noble, do not enter into chemical reactions and therefore it is extremely difficult, expensive and in many cases simply impossible to use them to create nanostructures – the basis of modern photonics.

Researchers from MIPT’s Laboratory of Nanooptics and Plasmonics have found a solution to the problem. Based on a generalization of the theory for so-called plasmonic metals, in 2012 they found that copper, as an optical material, is not only able to compete with gold, but it can also be a better alternative. Unlike gold, copper can be easily structured using wet or dry etching. This gives a possibility to make nanoscale components that are easily integrated into silicon photonic or electronic integrated circuits. It took more than two years for the researchers to purchase the required equipment, develop the fabrication process, produce samples, conduct several independent measurements, and confirm this hypothesis experimentally.

“As a result, we succeeded in fabricating copper chips with optical properties that are in no way inferior to gold-based chips,” says the research leader Dmitry Fedyanin. “Furthermore, we managed to do this in a fabrication process compatible with the CMOS technology, which is the basis for all modern integrated circuits, including microprocessors. It’s a kind of revolution in nano photonics.”

The researchers note that the optical properties of thin polycrystalline copper films are determined by their internal structure, and the ability to control this structure, achieve and consistently reproduce the required parameters in technological cycles is the most difficult task. However, they have managed to solve this problem demonstrating that it is possible not only to achieve the required properties with copper, but also that this can be done in nanoscale components, which can be integrated both with silicon nanoelectronics and silicon nanophotonics.

“We conducted ellipsometry of the copper films and then confirmed these results using near-field scanning optical microscopy of the nanostructures. This proves that the properties of copper are not impaired during the whole process of manufacturing nanoscale plasmonic components,” says Dmitry Fedyanin.

These studies provide a foundation for the practical use of copper nanophotonic and plasmonic components, which in the very near future will be used to create LEDs, nanolasers, highly sensitive sensors and transducers for mobile devices, and high performance optoelectronic processors with several tens of thousand cores for graphics cards, personal computers, and supercomputers.

Veeco Instruments Inc. announced today the launch of the new TurboDisc K475i Arsenic Phosphide (As/P) Metal Organic Chemical Vapor Deposition (MOCVD) System for the production of red, orange, yellow (R/O/Y) light emitting diodes (LEDs), as well as multi-junction III-V solar cells, laser diodes and transistors.

“Veeco continues to drive innovation with MOCVD technology that enables us to lower manufacturing costs and increase production with systems that are reliable, flexible and easy to use,” said Shuangxiang Zhang, General Manager of Yangzhou Changelight Co., Ltd.

According to research firm Strategies Unlimited, R/O/Y LED demand is expected to grow at a 10 percent compound annual rate through 2023. This demand for red, orange and yellow LEDs is being driven by signage, automotive, display and general lighting applications, as well as the emergence of new applications such as wearable smart devices.

Incorporating proprietary TurboDisc and Uniform FlowFlange MOCVD technologies, the new K475i system enables Veeco customers to reduce LED cost per wafer by up to 20 percent compared to alternative systems through higher productivity, best-in-class yields and reduced operating expenses.

Veeco’s proprietary Uniform FlowFlange technology produces films with very high uniformity and improved within-wafer and wafer-to-wafer repeatability resulting in the industry’s lowest cost of ownership. This patented technology provides ease-of-tuning for fast process optimization and fast tool recovery time after maintenance enabling the highest productivity for applications such as lighting, display, solar, laser diodes, pseudomorphic high electron mobility transistors (pHEMTs) and heterojunction bipolar transistors (HBTs).