Samsung’s Micro LED modular TV ‘The Wall’ has brought a new wave of attention for Micro LED. This next generation display technology, considered in some way better and more reliable than OLED, has currently been under development by high-tech companies around the world.
Micro LED displays have plenty of advantages, such as high brightness, compactness, and color contrast, and outstanding durability of heat, that make them suitable for a myriad of applications. However, those advantages reflect the difficulty level of manufacturing Micro LED. It requires technologies from both the LED and semiconductor industries to bring it into existence.
Some might wonder whether it will supplant OLED. The answer is negative as much as it can possibly surpass OLED in terms of share in some markets such as large-sized displays and automotive displays once it takes off.
One factor that should really be taken into consideration is time. Micro LED developers are running against time. While they are developing Micro LED, OLED and other display technologies are also undergoing refinement. The chairman of Mikro Mesa once said Micro LED would be able to change the game if it can be officially rolled out in 500 days.
Most of the companies that are developing Micro LED aim at two markets—the large-sized display and near-eye application markets. For those who target the former, they have to overcome challenges to successfully mass transfer Micro LED chips; while for those eyeing the latter, they have to make sure the brightness of their inventions are high enough to present clear images under outdoor ambient light.
Large-sized display, AR near-eye device, and automotive head-up display (HUDs) are markets where the Micro LED supply chain picks first to create enough revenue to support further researches on the feasibility of Micro LED technology being applied to other applications. According to LEDinside’s latest research report, Micro LED is projected to generate a market value of USD 2.891 billion by 2025, 68% of which will be contributed by large-sized Micro LED displays.
Related reading: All You Need to Know About Micro LED in 1H17
Taiwan holds a broad range of advanced LED and display technologies and that makes it top of the list of Micro LED developers. It is building a pilot line and aims to deliver Micro LED offerings to domestic VR companies in 3Q18. Epistar, AUO, Innolux, PlayNitride, and Macroblock tries to expedite their development. Meanwhile, Epistar along with some other LED makers such as EVERLIGHT also plans to mass produce Mini LED for smartphone backlights and fine-pitch displays. It anticipates a segmental revenue from Micro LED in the next five years.
China started Micro LED development slightly later. San’an Optoelectronics began related R&D two years ago. OLED display manufacturer BOE last year said it has also added Micro LED to their future product list and has seen preliminary results. In addition, KDX in 2016 announced to invest USD 35 million in Ostendo, which invented the quantum photonic imager (QPI).
A research team led by Dr. Zhaojun Liu completed 7 generations of Micro LED development—passive matrix (PM) Micro LED arrays, active matrix (AM) Micro LED arrays, small-scale chip transfer, large-scale mass transfer, devising displays using UV and RGB Micro LEDs, and rendering both monochromatic and full color images.
Prototypes from Korean firms debuted at CES 2018, namely ‘The Wall’ from Samsung and Micro LED displays from Lumens, proved the great effort both Korean enterprises and academics have put in. National research institutes KIMM and KAIST invented the roll-to-plate transfer technology and flexible vertical Micro LEDs (f-VLEDs) respectively.
As for Japanese companies, they work on not only Micro LED manufacturing technologies but inspection methods intended for Micro LED. Toray Engineering devised a photoluminescence-based testing solution that is able to monitor component quality at multiple production phases.
Developers in North America have close relationships with Taiwanese ones. Apple has reportedly been in collaboration with TSMC to develop applications based on silicon-based backplanes to sidestep the mass transfer bottleneck. It has even been granted a patent covering a foldable iPhone containing a Micro LED display layer. eLux, funded by Foxconn, teams up with AOT to transfer Micro LED chips sized smaller than 50μm.
Startups VueReal and Lumiode are targeting applications with small displays, including AR devices, projectors, and HUDs. With its proprietary pixel design and transfer technology, VueReal also plans to offer larger samples for smartphones and TVs once it completes product verification this year. On the other hand, Idaho-based Rohinni picks the keyboard backlight and automotive lighting markets to penetrate with its microscopic LEDs (250 microns long, 125 microns wide, and 80 microns tall).
In Europe, semiconductors companies and equipment providers weighed in. Allos Semiconductors and Veeco jointly demonstrated 200mm GaN-on-Si blue and green Micro LED wafers. The CEO of Allos Semiconductors promoted silicon over sapphire for Micro LED production, which resonates with perspectives from the CTO of UK-based Plessey Semiconductor. He contended GaN-on-Silicon is the only solution and silicon offers better thermal conductivity than sapphire.
France-based Soitec devised a new substrate the InGaNOX, on which different colored LEDs can grow together. In that way, RGB Micro LEDs can be driven at the same voltage level.
In August 2017, Google was reported to invest USD 15 million in glō to focus on the development of Micro LED display for smartphones and smart watches. Glō was tight-lipped over the partnership and its development of nanowire-based LEDs, while it was said in a press release from AIXTRON that glō-USA, Inc. placed an order to purchase MOCVD systems for Micro LED production.
Here at the end LEDinside listed out companies worldwide that have tapped into the development of Micro LED and what they have achieved so far. This up-to-date table covers the majority of the activities happening within the global Micro LED developing force. LEDinside will surely continue to keep an eye out for any potentially upcoming news.
[Editor's Note: A revision was made at 11:58 am, February 9th 2018. The table is updated with a few corrections about Macroblock, Innolux, Harvatek, Veeco, and AIXTRON. LEDinside would like to apologize for the confusion. Please contact news@LEDinside.com for further inquiry regarding the article.]