As the next generation display technology, MLED (Mini/Micro LED) attracts domestic and foreign display enterprises to actively layout. Driven by the huge market potential, accelerating the upgrading of MLED display technology and accelerating its commercialization has become an industry aspiration.
Ouyang Zhongcan, an academician of the CAS Member, recently pointed out when attending the production ceremony of an enterprise that China's semiconductor display has a strong industrial foundation and a complete led industrial chain. With the leading TFT design and manufacturing technology, mature semiconductor chips, advanced mled technology and strong policy support, mled technology will take the lead in realizing industrialization in China.
The advantages of MLED technology are popular
With the further popularization of 5G, ultra-high definition, artificial intelligence, AR/VR and other new technologies, display, as one of the important windows for human-computer interaction and receiving information, has more diversified applications.
Faced with the new requirements of industry integration and innovation on display technology, panel enterprises need to accelerate the development of a new generation of display technology with better performance to achieve innovative applications that meet the requirements of ultra-high resolution, super large size, functional integration, flexibility or transparency.
MLED not only has excellent performance in brightness, contrast, response speed, power consumption, life and flexibility, but also can realize the application from micro display to super large size display by changing the size of light-emitting chips and the distance between pixels and using different processing precision processes. It can provide more differential solutions for the display terminal market and create new application scenarios, Meet the diversity requirements of different display products and application scenarios.
"These advantages make MLED technology popular, and gradually become the most concerned next generation new display technology, attracting domestic and foreign display enterprises to actively layout." Ouyang Zhongcan pointed out that.
Today, many MLED global first products and prototypes have been launched at home and abroad, covering AR/VR, watches, car/NB, TV/business display and many other aspects, demonstrating the excellence and application potential of MLED technology.
As MLED continues to expand new applications in the display field, high-end large size TV, wearable display, AR/VR, vehicle mounted display, etc. will become rapidly growing fields, bringing new development opportunities for MLED display.
Million Insights estimates that the global Mini LED market will reach 5.9 billion US dollars in 2025, with a compound growth rate of 86.60% from 2019 to 2025; In the field of Micro LED, according to IHS forecast, the global shipment of Micro LED monitors will reach 15.5 million units in 2026, with a compound annual growth rate of 99.00%.
Driven by the huge market potential, accelerating the upgrading of MLED display technology and accelerating its commercialization has become an industry aspiration.
China's MLED industry has a strong foundation
At present, China's LED display industry has been located in the world's first echelon, forming a relatively complete LED industry chain and industrial cluster, covering terminal applications, panel manufacturing, packaging, chips, core materials and equipment and other fields.
In 2020, the output value of Chinese Mainland's LED industry chain reached 701.3 billion yuan, of which the output value of LED display applications was about 19.3 billion yuan.
At the same time, China is also the world's largest LED chip R&D and production base. Chinese enterprises have strong LED chip manufacturing capabilities and technological innovation capabilities, and LED chips are a key component of MLED technology.
Ouyang Zhongcan believes that with the leading TFT design and manufacturing technology, mature semiconductor chips and advanced MLED technology, MLED technology will be the first to realize industrialization in China.
In addition, China's policy support for MLED display industry is strong.
From top-level industrial design to standardized layout, to structural optimization and many other aspects, China has introduced relevant policies to strengthen the guidance and promotion of MLED display industry, so as to attract more upstream materials, devices and downstream module enterprises to join, continue to expand the overall scale of the industry, and initially show the advantages of industrial agglomeration.
Ouyang Zhongcan pointed out that the rapid growth of related industries will be accelerated as the leading enterprises of the industry chain are put into production. Under the effect of industrial chain synergy, Chinese enterprises can quickly reduce the cost of MLED and stride towards the consumer application market.
MLED may develop towards Nano LED in the future
Although MLED direct display technology has outstanding advantages, there are still many technical bottlenecks to be broken at this stage. Ouyang Zhongcan introduced, such as poor epitaxial growth uniformity, low LED chip efficiency, low yield and long time of massive transfer, among which the massive transfer technology is a key link.
The so-called "massive transfer" is the process of correctly and efficiently moving millions or even tens of millions of ultra micro LED crystals onto the circuit substrate after the fabrication of micron LED crystals. Taking 4K TV as an example, 4K usually refers to 4096 × 2160 resolution, assuming that each pixel is 3 R/G/B grains, it is necessary to transfer up to 26 million grains to make a 4K TV.
At present, a large number of transfer technologies include elastic seal micro transfer technology, laser transfer technology, and fluid transfer technology. However, these technologies are not mature enough, and the yield and transfer efficiency cannot reach the level of MLED mass production, which further drives up the manufacturing cost, leading to the high price of current MLED products. In particular, the micro transfer technology of elastic seal requires a large number of repeated seal actions to print red, green and blue, which is inefficient.
In this regard, Ouyang Zhongcan pointed out that in the future, MLED direct display may consider directly manufacturing red light, blue light and green light in integrated circuits according to design. "MLED direct display should follow the chip approach, and chip practitioners should consider MLED direct display in future design."
In addition, MLED faces new technical challenges in materials, equipment, chips, driver IC, backplane design and packaging.
"In order to enrich the display application scenarios and achieve more delicate visual effects, the chip and package size in LED display show a trend of miniaturization. MLED display technology may develop into Nano LED (QNED) display technology in the future." Ouyang Zhongcan emphasizes.
It is worth mentioning that domestic enterprises have innovated and developed COG MLED packaging process based on the original SMD and COB packaging technology, with packaging process as the key point. COG MLED backlight technology has the advantages of constant current drive, high brightness, high contrast, non flickering and high splicing flatness, and is expected to become the mainstream of the future display industry.