[ Security Exhibition Network Current Affairs Focus ] In the past year, with the maturity of Mini / Micro LED, issues related to its definition, technical route or upcoming industry changes have caused countless discussions and even arguing.
History has confirmed that there are some questions that time will give answers, and some questions that science can give positive solutions. Nineteenth-century French writer and "father of science fiction" Jules Verne said that you only know the answer if you explore.
How to define Mini / Micro LED?
There is no one-size- fits-all answer to this question. Every company has a view, and the head companies pay their "personalized interpretation" to each product.
The more common definition at this stage is based on the size of the LED chip, that is, the Mini LED chip size is 50-200 microns, and the Micro LED chip size is less than 50 microns. In addition, there is a consensus in the LED industry chain that displays
below P2.5 are defined as small pitch, P0.5 enters Micro LED, and Mini LED is in between.
During the national tour of the new display of advanced engineering, Gong Wen, chairman of Jingtai Co., Ltd. expressed his opinion on this. The LED industry chain companies usually define Mini / Micro LED based on the industry in which they are located. This is self-explanatory. This definition should be more From the perspective of the end consumer. In this regard, Chen Yongming, general manager of Hongli Display also believes that "Mini / Micro LED needs to be defined from the application terminal."
Qin Kuai, the technical director of Guoxing Optoelectronics' RGB business unit, has a different opinion. He said that Guoxing Optoelectronics tends to define Mini LED from the application market, and P1.0-0.1 are the application scope of Mini LED. Shao Pengrui, technical director of Jintai, believes that from a narrow sense, P1.0-0.3 is Mini LED and P0.3 and below are Micro LED.
There are many different definitions from the above. Behind the controversy over the definition of Mini / Micro LED, on the one hand, there is not yet a platform with sufficient credibility to define Mini / Micro LED, on the other hand, it indirectly highlights the enthusiasm of LED industry chain companies for Mini / Micro LED investment, and the future display The continuous pursuit of technology.
Formal vs Flip
As the distance between dots grows, it is generally agreed that flip chip has advantages. A number of people in the LED industry chain told senior engineers of the new type of display that it is only a matter of time before flip-chips can replace full-length displays.
Compared with the front-mounted chip, the flip-chip has excellent heat dissipation, high light output efficiency and high reliability, which is suitable for high-power products. At the same time, flipping reduces the number of links including welding wires, which increases production efficiency and breaks the upper limit of the pitch of the positive mounting points. According to Li Peng, vice president of Huacan Optoelectronics, "From a chip perspective, small-pitch is using a front-loaded chip, Mini RGB is using a flip-chip, and Micro LED is a flip-chip with a vertical structure chip."
Quan Jinsong, the president of Zhaochi Energy Conservation Co., Ltd. said, "When the pitch reaches P0.6, formal dressing can no longer be done." Qin Kuai, the technical director of Guoxing Optoelectronics' RGB Division, also said that when the pitch goes down, only flip chips can be used.
Shao Pengrui, technical director of Jingtai Co., Ltd. believes that in the mass production of Mini LED above P0.9, the full flip-chip solution has a longer life cycle than the full-package solution. In addition, Wang Yang, deputy general manager of Xida Electronics, pointed out that COB integrated packaging is the only way to achieve ultra-high density display in flip Mini LED and flip Micro LED.
Of course, flip-flops and dresses are not a one-on-one relationship. In different application scenarios, each has its own advantages. At this stage, the formal mounting process is mature and the cost can be controlled, while the flip chip is not used on a large scale and the process is still being continuously improved, and the cost is relatively high. Shao Pengrui also pointed out, "From the perspective of market cost, the large-scale mass production schedule of the full flip-chip solution will be delayed."
Which technical route is better, SMD, IMD, COB?
Because SMD is close to the upper limit of the small pitch, it is rarely used in Mini LED. IMD and COB are the mainstream packaging technologies for Mini LED at this stage.
On the whole, IMD and COB each have their own advantages and disadvantages, and they are in a continuous improvement stage. Among them, IMD is considered to be a transitional type of packaging technology, because it does not fundamentally solve the problems of SMD including false welding, protection, repair, caterpillars, etc .; COB is accused of being difficult to repair, obvious seams, and poor consistency. And high costs. Based on this, packaging companies that mainly promote IMD or COB have launched corresponding solutions accordingly.
Qin Kuai, the technical director of Guoxing Optoelectronics' RGB division, believes that IMD is a solution for the rapid industrialization of Mini LED displays. Jingtai Technology Director Shao Pengrui believes that the cost of Mini LED represented by IMD is difficult to exceed. Tu Menglong, technical director of Lehman Optoelectronics, said that COB has more cost advantages and good stability, and can achieve the development of dot pitch.
Li Haifeng, general manager of Xida Electronics Shenzhen Branch, pointed out that the choice of technology route is mainly based on their own positions, not purely technology-oriented. In this process, the choice of head companies often determines the direction of the market. Qin Kuai admits that each technology has its own strengths and weaknesses, and the key depends on the satisfaction of the end market.
Who will go further for Mini / Micro LED and OLED?
Gone are the days when LCDs formed market share. Mini / Micro LED and OLED will continue to develop in their respective application areas. In overlapping application areas, the key lies in who will occupy the cost advantage faster.
However, the new display of Gaogong believes that OLED is only a "feast of luxury," and Mini / Micro LED is a "revelry for the whole people" (click through to the original text).
The threshold for OLED investment is high. The investment for a 6th generation flexible AMOLED production line is about 40 billion yuan, and key materials and equipment are mainly imported. At present, there are only about 10 companies that can achieve mass production of OLEDs worldwide. In addition, Gong Wen, chairman of Jingtai Co., Ltd. pointed out that as an organic substance, OLED has disadvantages. OLEDs have short lifespans, burn-in issues, and other issues that panel manufacturers are constantly improving.
Relatively speaking, Mini / Micro LED has lower entry barriers under the domestic mature LED industry chain. According to the statistics of the new display of advanced engineering, among the 11 Mini / Micro LED related investment events that occurred in 2019, the cumulative investment amount was about 50 billion yuan.
At this stage, both Mini / Micro LED and OLED are breaking through cost and mass production issues. As a powerful supplement to the OLED application market, panel makers including BOE and TCL Huaxing are also actively deploying Mini / Micro LED.
In the Mini / Micro LED era, how does the industry chain change?
During the national tour of high-tech new displays, many LED industry chain companies have stated that the industry chain will definitely change when entering the Mini / Micro LED era. Among them, LED packaging and LED display
companies may be marginalized, while LED chip companies seem to be "satisfied."
Yang Canyuan, the manager of Easystar R & D Department, believes that from Mini LED to Micro LED, the development of the industry will present a "big combination" trend, and chips, packages and applications no longer exist independently. When packaging companies begin to ship modules, the participation of display companies may be greatly reduced. Guangxiang Technology Deputy General Manager Xiong Jian also said that Micro LED will reshape the industry, and display companies are in danger.
A representative of a leading LED packaging company believes that there is a possibility that chip companies and display companies will join hands to "crowd out" LED packaging companies.
In this regard, Leiman Optoelectronics Technical Director Tu Menglong said that either the packaging company is developing downwards or the display company is developing upwards. However, Gong Wen, chairman of Jingtai Co., Ltd., has different views. Jingtai Co., Ltd. will not expand the display business. He said that the surgery industry has a specialization, in addition to technical issues and market issues, "besides technical acceptance, the downstream also plays a role of distribution." Quan Jinsong, president of Zhaochi Energy Saving, also said that the company does not have this (downstream) idea .
In fact, entering the Mini / Micro LED era, LED industry chain companies are almost "everyone at risk." Chip companies that seem to be at a high position need to deal with the dilemma of continued decline in general product prices and accelerate the shift to Mini / Micro LED on the other hand to enhance competitiveness. Of course, besides Mini / Micro LED, LED displays have great potential for different application scenarios.