MicroLED Will Become the Future of Display Screens?

Not long ago, the MicroLED display, which had only existed in display cabinets and PPT, finally entered the formal mass production stage. At the beginning of its appearance, the MicroLED technology was considered to be the first display technology without size limitation in history, and it has become the recognized future development direction of display screens, so it is strongly sought after by manufacturers in the entire display industry chain.

The basic characteristics of Micr OLED technology are excellent: this reality technology has a wide color gamut, high brightness, low power consumption, high stability, long life, wide viewing angle, high dynamic range, high contrast, high refresh rate, transparency, and support Features such as seam connection and integrated internal sensors. Although these characteristics are realized on LCD, OLED and QD panels respectively, MicroLED technology can realize these technical characteristics at one time, and there are almost no obvious shortcomings. It is currently the most comprehensive display panel technology under technical conditions. All parties in the pursuit of breaking the game are promoting the development of MicroLED. Due to competitive costs and advantages in the downstream industry chain, the main LCD (liquid crystal panel) production capacity worldwide is now concentrated in mainland China. In Jingdong underway, led by domestic enterprises in their efforts, we share in the LCD market has been in the last year (2019) broke the 50% win half of the global LCD market.

In contrast, the market share of traditional LCD manufacturers is rapidly shrinking: Samsung Display (SDC) has announced earlier that it will close its own LCD production line and focus on the development of QD LCD (quantum dot) and OLED technology and shortly after, another South Korean giant LG Display (LGD) followed suit and shut down its domestic LCD production line. In addition to these two major Korean manufacturers, Japanese LCD representatives Panasonic and JDI will gradually withdraw from the business. Taiwanese enterprises such as AUO and Innolux are also continuously reducing their investment in LCD production lines. In the OLED field, Korean manufacturers headed by Samsung and LG firmly control the entire industry chain. They have great advantages in terms of effective production capacity, upstream materials and equipment, downstream applications and supply chains.

In the upstream of the industry, both Samsung and LG have their own material and equipment production capabilities and have a strong technical foundation. In the downstream application market, Samsung and LG dominate the small and medium-sized and large-sized OLED panels respectively. Samsung's tremendous advantages in small and medium-size panels, OLED panels which can be directly used on their own products, light Samsung smartphones in the global market share is enough to make them a popular hot drink. As for large-size OLED panels, LG will also directly apply panels to large-size display devices (including but not TVs ). In addition to their huge internal demand, their products also firmly occupy the high-end market of the entire industry. Owning a broad downstream application market and the advantages of the entire industry chain that other competitors do not have, and allowing them to obtain richer application experience and technical support for their OLED panels, it is naturally better than BOE and JDI, which can only provide panels for the time being. Competitiveness.

As for the core material supply and equipment manufacturing of upstream display panels, Japanese and German companies still have very strong capabilities, and these advantages can be applied not only to LCD and OLED but also to other new display technologies. In addition to traditional display panel manufacturers advancing, downstream manufacturers such as Apple are also participating in the development and manufacturing of this technology, and the number and fields of participants following MicroLED technology are increasing. Although MicroLED is currently not their main focus, they will increase investment in this field to ensure that they can catch up when MicroLED really takes off, and avoid being stuck by upstream manufacturers. Under the premise that the LCD and OLED markets have been divided and there is not much left, participating in the development of next-generation display technology can bring new competition opportunities to all parties, and can also break the current regional clusters and advantages to form new Industrial structure. Therefore, having the opportunity to break the game is the primary reason why MicroLED technology has been vigorously promoted by all parties since its inception.

Shift the focus of development

According to public information, the MicroLED industry has received a huge cumulative investment of more than 5 billion U.S. dollars. Patent applications, prototype products brought by suppliers and technology disclosures of display suppliers have also increased in the past two years. According to public information, Samsung, LG, Sony, TCL, Konka, Sharp, BOE, China Star Optoelectronics, Sanan Optoelectronics, Tianma, AUO, Glo, Kyocera, PlayNitride, RiT display, Jade Bird ( JBD), VueReal (a Canadian startup), Plessey (a British company, VR and MR screen supplier) and other companies have launched related products based on this technology. This kind of contending situation is obviously more dynamic than the current basically solidified LCD and OLED market. However, the technology that can be used for large-scale mass production is very different from the product prototype in the laboratory. Although MicroLED technology has reached the corresponding technical indicators and characteristics in various experimental conditions, there is still a lot of distance from entering the actual commercial stage.

Among the information disclosed by the manufacturers, only the company from Taiwan Province currently claims to be able to achieve a 100% yield, but there is still no corresponding specific mass-produced panel product. The current main challenges of this technology are also focused on improving the production process and reducing production costs. For example, traditional LEDs can easily achieve an external quantum efficiency (EQE) of about 70%, while micro-LEDs less than 10 µm may struggle to achieve 20%. Red LEDs have low EQE and fragile characteristics, which are particularly challenging. Because the MicroLED unit is too small, it directly leads to a substantial increase in the surface area of ​​each unit on the final cost panel, which also greatly increases the complexity of manufacturing and brings more potential problems. It is necessary to maintain high efficiency while mass production. , To reduce chip size and improve chip design and manufacturing processes.

The production of final MicroLED display products (mobile phone screens, TVs, displays, etc.) also involves more technologies and processes, including epitaxy, lithography, chip manufacturing, substrate removal, inspection, mass transfer, bonding and interconnection, and testing, Maintenance, backplane and driver IC, etc. After years of development, although many technical problems have been solved and the technology has become more mature, more process challenges have also been found in the manufacturing stage. A few years ago, the main development goals of the chip industry were to improve the process technology, reduce the chip area, and increase the energy consumption ratio. In recent years, more and more comprehensive directions such as AI, auxiliary chips, and special chips have been put in place, advocating to improve the processing capabilities of chips from the perspective of specific applications and the overall situation, instead of blindly improving computing performance. Therefore, companies in the MicroLED industry are increasingly focusing more on technologies such as overall optimization, image improvement, application scenario matching, and mass production equipment, rather than blindly pursuing what this technology can bring The performance limit. These practical trends have also effectively promoted the practical value of this technology and further promoted its commercialization process.

Application potential of MicroLED display

The demand for MicroLED displays can be analyzed from two aspects: the first is to replace current products on the market as a better-performing reality technology, and the other is to develop some new display application scenarios with this new technology. For the first scenario, MicroLED is used in augmented reality/mixed reality (AR/MR), virtual reality (VR), ultra-large video displays (100 inches or more), TVs and monitors, car displays, mobile phones, smart watches, and Wearable devices, tablet computers and laptops have very broad application prospects. In the current display market, although new technologies such as OLED and quantum dots are emerging differently, LCD panels still occupy an absolute leading position in the entire market. However, due to technical limitations, LCD screens are basically under 65 inches in size. To further expand the size seems a bit powerless. While OLED is currently accelerating its popularity in the smartphone market, and its market share is increasing, but it is currently mainly used in high-end products. The situation of quantum dot technology is similar to that of OLED. It is currently mainly used in high-end display products. LEDs are mainly used in large displays.

In order to compete with these "traditional" technologies, MicroLED should determine its unique market value to highlight its advantages and give better play to the characteristics of these technologies. MicroLED can be customized in size just like LED. At present, Samsung launched a 583-inch product The Wall at this year's CES, but this product is not strictly a MicroLED TV. According to the standard definition, the size of the LED light-emitting unit on the MicroLED panel should be less than 50 microns, the LED light-emitting unit of the MiniLED TV should be less than 100 microns, and the smallest size of Samsung's The Wall series TV is also 80 microns, which is also limited by current manufacturing A compromise product of craftsmanship and cost. Coupled with the exaggerated cost and price of these large-size products, there is still a long way to go before entering the ordinary consumer market. It can be seen that the greatest advantages of MicroLED products may not be fully utilized in the initial stage. In order to improve cost competitiveness, the initial MicroLED should be the first Used on small screens such as smartwatches.

To create a new display market, MicroLED needs to provide some functions that other alternative products cannot enable, including some displays with customized shapes and displays that need to integrate various sensors. As an emerging display technology, MicroLED has gained widespread attention by virtue of its versatile display performance and the advantages of highly integrated current mainstream displays. However, MicroLED is still limited by many bottleneck technologies, especially in the manufacturing process. Even if the industry can make a breakthrough, it will take a lot of time to achieve true mass production and commercial use.