There is an emerging type of display: the Micro-LED display, which has the potential to become the next-generation mainstream, thanks to its ability to be manufactured in sizes ranging from tiny to enormous. The challenges and opportunities are analyzed in the IDTechEx report "Micro-LED Displays 2021-2031: Technology, Commercialization, Opportunity, Market and Players.".
COVID-19 has not halted the development of Micro-LED displays. With CES and Display Week, as well as a series of online events, we can see that the progress and new releases of Micro-LED display prototypes and products are not significantly affected.
The growing number of activities by display suppliers can be seen in the highly accumulated investment and the increasing number of patent applications, as well as in the prototypes/products submitted by Micro-LED suppliers such as AUO, PlayNitride, RiTdisplay, Samsung, LG, Sony, TCL, Tianma, Konka, Glo, Plessey, JBD, X-Display, VueReal, CSOT, Sharp, Kyocera; the list goes on.
However, prototypes used to test technological/scientific readiness for laboratory/manufacturing-scale production are very different from mass-produced commercial products. The latter require zero defects for consumer goods. Although the science is proven, there are more engineering and manufacturing challenges. For example, conventional LEDs can achieve external quantum efficiencies (EQE) of up to ~70%, while tiny micro-LEDs smaller than 10 µm can struggle to reach 20%. Red LEDs are particularly difficult, as they have a low EQE and are fragile. Tiny micro-LEDs have a large surface area, which can lead to more defects during the manufacturing process. Therefore, it is important to address the engineering/manufacturing challenges, including miniaturizing the array size while maintaining high efficiency, improving chip design, and enhancing chip manufacturing techniques. Other issues include mass transfer performance and accuracy, defect repair, testing, uniformity, light management, color conversion, etc.
Manufacturing a Micro-LED display involves numerous technologies and processes, including epitaxy, photolithography, chip fabrication, substrate removal, inspection, mass transfer, bonding and interconnection, testing, repair, the motherboard, and the drive IC. After years of development, some technological difficulties have been overcome, while new challenges have emerged. For example, several years ago, the main focus was on die miniaturization, chip design, and mass transfer. Recently, more and more players have realized that the key lies in a comprehensive understanding of all processes. Therefore, an increasing number are dedicating resources to technologies such as inspection, repair, drive, image enhancement, light management, and high-volume production equipment.
Another interesting phenomenon is the growing number of partnerships, mergers, acquisitions, joint ventures, and new investments. This aligns with the display cycle trend. A year or two ago, Micro-LED displays were undergoing a major rollout, and now the key players are gradually finding their footing. Many suppliers have shifted their focus to mini-LED displays and large billboards and televisions, while companies continue to work on Micro-LED displays. Compared to previous years, consolidation is becoming more pronounced.
Continuing with the LCD industry, China has invested heavily in micro-LED displays again. Before 2019, BOE was not active in the micro-LED display field. However, after 2019, BOE jumped to the top spot in terms of patent filings. This significant investment also indicates strong interest. Although there are quite a few startups in Europe and America, it appears that East Asia will dominate the development of micro-LED displays.
