Packaging, the eternal topic of the LED industry, as a connection point between the upstream and downstream industries, plays a role in the transformation and integration. At the moment, the LED packaging method is all-encompassing, and the COB display technology has become a new “process direction” that has been promoted by major LED screen enterprises. Manufacturers have increased their investment in the COB small-pitch LED displays market. As a result, the major technical achievements of COB have come strong.

COB products will account for more than half of the small-pitch LED market by 2020

According to industry experts, COB products will account for more than half of the small-pitch LED market by 2020. Under the logic of “COB is the future”, the 2018 COB supply scale and the number of participating brands will increase significantly. . Then, in the current era of urgent innovation in the industry, can COB packaging open a new trend in the industry and become a new economic growth point?

The advantages of COB technology are outstanding. The challenges encountered cannot be ignored.

In recent years, the packaging industry has been in the fast driving and development stage of new materials and new processes, and new display technologies emerge one after another. The most striking of them is the COB package. Therefore, all major LED screen enterprises seized this potential business opportunity in time. At the Guangzhou LED Exhibition in 2018, industry giants such as Absen and Leading launched the latest research and development COB small-pitch display products, which received a lot of attention from the industry. . Being able to be so widely accepted, of course, is not groundless, the application advantages of COB package on LED display are reflected in all aspects.

First of all, it has the characteristics of ultra-thin, anti-collision and anti-pressure, and strong heat dissipation. According to the actual needs of customers, PCB board with thickness from 0.4-1.2mm can be used to reduce the weight to 1/3 of the original traditional products. Significantly reduce the cost of structure, transportation and engineering for customers; COB products directly encapsulate the LED chip in the concave lamp position of the PCB board, and encapsulate it with epoxy resin. The surface of the lamp point is convex into a spherical surface, smooth and hard, and crash resistant. Wear-resistant; COB products are printed on the PCB board, the heat of the wick is quickly transmitted through the copper foil on the PCB board, and the thickness of the copper foil of the PCB board has strict technical requirements, plus the immersion gold process, almost It will not cause serious light attenuation, so there is very little dead light, which greatly extends the life of the LED display.

Secondly, the bendability and bendability are unique features of the COB package. The bending of the PCB does not cause damage to the packaged LED chip. Therefore, the LED arc screen can be conveniently fabricated using the COB module. Shape screen. It is an ideal substrate for personalized screens in bars and nightclubs. It can be seamlessly spliced, the production structure is simple, and the price is far lower than the LED shaped screen made by the flexible circuit board and the traditional display module. All-weather excellent is also the biggest feature of COB. It adopts triple protection treatment. It has outstanding effects of waterproof, moisture, rot, dust, static electricity, oxidation and ultraviolet light. It can meet the working conditions of all-weather conditions. The temperature difference between minus 30 degrees and 80 degrees above zero can still be used normally.

The emergence of a new product and new technology has never been smooth, and there are always many obstacles on the way. The COB and COB packaging technology also faces several challenges. The package has a low pass rate, low contrast, high maintenance cost, etc.; its color uniformity is far less than that of a SMD device with a spectral separation; the existing COB package still uses a positive chip, which requires a die bond. The wire bonding process, therefore, has many problems in the wire bonding process and its process difficulty is inversely proportional to the pad area. Finally, the manufacturing cost problem is also a major challenge for COB. Due to the high defect rate, the manufacturing cost far exceeds the SMD small pitch.

Is the Mini LED a threat? The combination of the two is the new trend
In addition to the challenges posed by COB’s own production problems, the emergence of Mini LEDs has also had an impact on COB packaging technology. From the attention of the COB package at the beginning of the year, to the Mini LED products launched by LED screen companies in the near future, the Mini LED has an infinite moment. At the Infocomm exhibition in the United States, Alto Electronics released the latest “Mini LED commercial display system” at the exhibition, which has achieved great repercussions, as well as the industry’s China Huaguang, Jingtai and Ruifeng Optoelectronics have also launched Mini LEDs. People have raised the heat of the Mini LED, which is bound to make the COB package a big blow.

actually not. Although many industry insiders have expressed their views on which Mini LEDs and COB LEDs will occupy the mainstream position of LED displays in recent years, the existence of the two does not conflict. By definition, COB is just a kind of packaging technology. COB LED is only the product of this packaging technology. Mini LED is an LED product with a dot pitch of about 100 microns, so the two are definitely not conflicting. At the same time, at this year’s US infocomm exhibition, a series of Mini LED COB products were unveiled at the US infocomm exhibition. Domestic industry giant Liard also said on the public platform that COB-type Mini LED small pitch products are being developed. This means that the two are not only competitive, but also have a good fusion and complementarity. The pitch of the Mini LED is too small. The traditional SMD packaging technology may not meet the packaging requirements of the Mini LED. The COB packaging technology may be a better choice.

The upgrading of technology is bound to bring about the upgrading of products. At present, COB packaging technology is the update direction of the packaging technology of Mini LED. As for whether the upgrade of the product reaches maturity, it depends on whether the final product form is modular. Panelized. The use of COB packaging technology to produce Mini LEDs will inevitably lead to technological changes from packaging to downstream. However, the current LED display industry production line still uses the previous SMD packaged production line. The burden of producing mature Mini LED products may fall on the shoulders of first-tier manufacturers in the industry. However, listed LED display manufacturers headed by Eliad, who has financial strength in China, can also deploy mature LED products with mature technology.

Policy, technology, and market all have future development just around the corner
At present, LED small-pitch display products have serious homogenization phenomenon. After years of development, SMD packaging technology has entered the bottleneck period, and has reached the ceiling in product spacing. At the same time, several pain points that users are very concerned about are expected to be improved, such as: dustproof and waterproof, anti-collision, product stability and reliability, etc., these users spend a lot of energy. From the classification of packaging technology, COB small-pitch LED is a small-pitch 2.0 era product, eliminating the need for SMD package lamp bead packaging, patching, reflow soldering, etc., stability and reliability have been greatly improved. In the high-end market such as the command and dispatch center, COB’s high stability, maintenance and maintenance convenience and viewing comfort will be highly recognized, and will bring more application space for the future development of COB in the market. .

Not only the advantages of the market and technology, COB technology is also the national “13th Five-Year Plan” key scientific research project – strategic advanced electronic materials. The main task of the new display project is to break through the shortcomings and limitations of traditional small-pitch LED display technology. When policies, technologies, markets, time, location, and people are fully equipped, COB technology should go forward and the future can be expected!

Technological innovation is an unchanging topic in the LED display industry. Only by continuously introducing new technologies and new products can we ensure the smooth completion of the industry upgrade. The emergence of COB technology, with small pitch LED products to a higher level, to bring a better user experience to the end market, but we can’t predict, there will be high-tech technology will wait for the LED display in the future What kind of surprises will the user bring to the screen industry? Let us wait and see!