LED Packaging: Basic Concepts and Development History

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On 02/13/2025

LED packaging refers to the process of assembling a light-emitting diode (LED) chip with supporting circuits, heat dissipation structures, and other components, and sealing them with packaging materials to provide protection and heat management. LED packaging technology has largely evolved from discrete device packaging technologies but carries significant differences. In general, discrete device chips are sealed within the packaging, with the primary purpose being to protect the chip and complete electrical interconnections. In contrast, LED packaging serves the dual purpose of emitting electrical signals while also protecting the chip for proper functionality.
The selection of packaging materials is critical for LED performance and reliability. Common LED packaging materials include organic materials, inorganic materials, and composite materials. Organic materials, such as epoxy resin and silicone, offer good light transparency and electrical insulation properties. Inorganic materials, such as aluminum nitride and silicon nitride, provide excellent heat conductivity and high-temperature resistance. Composite materials combine the benefits of both organic and inorganic materials. Over the past 40 years, LED packaging technologies have advanced significantly, with various types coexisting, including Lamp, SMD, IMD, COB, COG, POB, GOB, and MIP. Among these, GOB is an upgraded coating technology for SMD devices, COG is an extension of glass substrate technology in COB packaging, and POB is commonly used for backlight module packaging.
In the field of small-pitch LED displays, SMD packaging technology remains the industry standard. For display modules with a pitch greater than P1.0, SMD remains an excellent choice. However, with increasing competition in the micro-pitch segment, traditional SMD packaging faces challenges in meeting the demands for displays with a pitch below P1.0, necessitating the development of new packaging technologies to meet the needs of the micro-display era.

Table of Contents

Lamp--has helped the rapid development of the LED display industry

Lamp (through-hole) packaging uses lead frames with various external pin structures, commonly referred to as the “frame,” where one end typically has an “oval cup” structure. The LED chip is bonded inside this cup, after which liquid epoxy resin is injected into the LED molding cavity. This is followed by insertion into the adhesive-bonded LED frame, and the assembly is subjected to high-temperature curing to form the final package, which is then separated into individual units.

The through-hole packaging structure was the first to be successfully developed and launched into the market. From early single-color and bi-color displays to the full-color displays emerging in the late 1990s, the Lamp packaging showed strong resilience. Outdoor LED full-color displays, known for their good sealing, high brightness, and environmental adaptability, dominated the outdoor display market before the rise of surface-mounted (SMD) technology. To this day, outdoor products with a pitch of P10 or above are predominantly Lamp-based.
Currently, through-hole packaged LEDs are mainly used in dot matrix displays, indicator lights, traffic lights, and outdoor grid displays. Initially, full-color LED displays used three or four Lamp LED devices in red, green, and blue for a single pixel. RGB three-in-one Lamp LED devices were later introduced to meet the high brightness, high resolution, and efficient stitching requirements. For outdoor large screens, Lamp-based LEDs are mainly used for displays with a pitch of P10 or greater, where their brightness and reliability advantages are significant. However, with the trend towards finer pitch in outdoor displays, through-hole devices have been gradually replaced by SMD technology for products with a pitch below P10.

SMD - the most mainstream packaging form currently used

Surface-mount device (SMD) packaging involves soldering one or more LED chips onto a metal bracket with a plastic “cup” frame. The frame is then filled with liquid epoxy resin or organic silicone, baked at high temperatures, and cut into individual surface-mount units. SMD packaging is highly automated, utilizing surface-mount technology (SMT). Displays using SMD components offer superior color reproduction, color consistency, uniformity, viewing angle, and overall image quality compared to through-hole displays. However, SMD packaging has inherent disadvantages, including higher failure rates, faster degradation, and relatively poor environmental adaptability.

Currently, SMD LEDs are classified into lead-type (TOP) LEDs and chip-type (Chip) LEDs. The former typically uses a PLCC (Plastic Leaded Chip Carrier) bracket, while the latter uses a PCB as the LED chip’s carrier. While PLCC brackets are cost-effective, they suffer from issues such as poor airtightness, thermal resistance, and uneven light emission. Despite the availability of higher-performing materials like PCT and EMC for brackets, these are less widely used due to their higher cost. Around 2010, SMD packaging gained widespread acceptance in the indoor LED display market, transitioning from leaded packaging in line with the broader electronics industry trend.

IMD (N in 1 LED) - the intermediate product of the transition from SMD discrete devices to COB

As the small-pitch LED display market approaches the P0.X era, where sizes have become nearly as small as possible, a new alternative emerged in the domestic industry: IMD integrated packaging (Integrated Mounted Devices, “IMD”) using “4-in-1” and “N-in-1” configurations. IMD involves integrating multiple RGB LEDs into a single small unit, creating a single “pixel” module. The main technical configurations include common anode 4-in-1, common cathode 2-in-1, common cathode 4-in-1, and common cathode 6-in-1, among others.

The advantage of IMD’s integrated packaging is that the individual LED sizes are larger, making surface-mounting easier and enabling smaller pixel pitches while reducing maintenance complexity. Compared to traditional SMD, IMD offers better collision resistance and higher mounting efficiency. It also has superior color consistency, binning performance, SMT process compatibility, and is easier to repair, making it an increasingly popular choice for many companies. The “4-in-1” package is viewed as a compromise between traditional surface-mount LEDs and COB products, combining the benefits of both SMD and COB technologies. One of the main benefits of this packaging is that it overcomes the technical challenges associated with having too many LED dies in a single-cell structure in COB packaging. For downstream manufacturers, the basic geometry of the packaging structure doesn’t shrink too much with smaller pixel pitches, preventing the “difficult soldering” problems associated with surface-mounting. Additionally, this well-proportioned packaging structure helps facilitate easier “bad light” repairs for small-pitch LED displays, even enabling “on-site manual” repairs—a feature that surface-mount products and COB modules don’t possess.
The most important advantage is that the IMD packaging solution significantly reduces the overall costs for display manufacturers. For example, with a pitch range from P0.9 to P0.5, the PCB can be simplified to a 6-layer, 2-stage configuration, and the SMT efficiency is more than three times higher than that of SMD. Moreover, for packaging manufacturers, the IMD solution can reuse most of the equipment from existing small-pitch production lines, requiring relatively low capital investment. Considering all these factors, IMD is a transitional technology between SMD discrete devices and COB, combining the advantages of both.

COB – Entering the Mass Production Phase

Around 2017, a new packaging process—COB (Chip On Board)—began to attract widespread attention. COB is a new type of packaging method that differs from traditional SMD surface-mount technology. Specifically, it involves adhering bare chips to a PCB using conductive or non-conductive adhesive, followed by wire bonding for electrical connections. The chip and wire bonds are then encapsulated with adhesive. The COB process includes steps like solder paste printing, die bonding, automated optical inspection (AOI), functional testing, rework, and encapsulation. COB packaging with flip-chip technology offers several advantages, such as better heat dissipation, higher reliability, and stronger protection, which reduces maintenance costs. COB technology overcomes the physical size limitations of packaging light-emitting chips as LEDs and mounting them onto PCBs. With its high stability and ultra-high-definition display characteristics, COB has become a promising emerging display packaging technology.

Major companies like Sony and Samsung were among the first to launch COB-based products. In China, companies like Hida Electronics, Leyard, and Zhongqi Optoelectronics also adopted COB technology. Later, leading brands and packaging companies such as Zhaochi, Hongli, Gaoke, Lanpu Vision, and Tengcai quickly followed suit. The introduction of COB technology marked the end of slow development in the LED display industry, ushering in large-scale, capital-intensive production. This shift effectively reduces costs and promotes the widespread application of COB technology in the market.
COB integrated packaging not only reduces bracket costs and simplifies the LED screen manufacturing process but also reduces chip thermal resistance, enabling high-density packaging. With flip-chip COB products, even the gold wire bonding is eliminated. LED displays with COB packaging expand the device’s heat dissipation area, allowing generated heat to dissipate more easily. From a cost perspective, COB LED display modules can save packaging costs compared to traditional methods.
In terms of market performance, COB packaging technology has steadily increased its market share in recent years. The year 2023 is considered the breakout year for COB products, especially in the small-pitch segment below P1.2, where COB is rapidly replacing SMD technology. Looking ahead, with the growth of large LED displays, more applications are moving toward products with pixel pitches below P1.0. Currently, the vast majority of LED displays with a pitch of P1.0 or less are using COB technology. Therefore, COB and its variants are closely tied to the future growth of the large LED display market. Industry experts predict that in the next five years, COB-based LED display products will maintain a high growth rate of 20-30% annually, becoming the leading category in the LED display industry.
As COB LED packaging technology solves the issue of bulk mounting for small-sized LED chips, it has been widely recognized as the technological development route for Mini/Micro LED products. The advancement of this technology will bring new innovations to the LED device packaging industry.

POB – Helping Mini LED Backlighting Breakthrough

POB packaging technology, or Package on Board, commonly referred to in the industry as the “Starry Sky” solution, first packages LED chips into individual SMD LED components and then mounts the chips onto a substrate. Currently, POB backlighting solutions are categorized based on the type of package used, including flip-chip SMD and CSP (Chip Scale Package). Among these, POB with SMD packaging is more mature, has relatively lower costs, and is highly scalable for mass production. However, it is limited by the size of the package, which generally has a larger OD value, making its application scope narrower compared to COB.

CSP is a chip-level package, typically about 1.2 times the size of the chip, allowing it to achieve a smaller OD compared to COB, with even lower costs. However, CSP packages have a very small chip size, and the electrode pads are very close to each other, which can lead to issues such as poor adhesive coverage, light leakage, uneven light mixing, and optical interference.
POB is currently one of the most widely used packaging technologies, especially prevalent in Mini LED backlighting display products. Its advantages include high maturity, the ability to meet most application packaging requirements, and relatively low technical demands. However, its main disadvantage is the relatively higher thickness of the backlight module, preventing it from achieving ultra-thin designs. Given the current technological state, Mini POB remains the mainstream solution, especially suited for applications like 4385-inch TVs and 1739-inch vehicle displays, offering good cost-effectiveness.
Although Mini LED backlighting has been growing rapidly, its development faces various challenges, including cost and packaging route issues. Specifically, the ongoing debate between POB and COB packaging remains at the forefront of Mini LED backlighting discussions. Some argue that while Mini POB is easier to manufacture and has strong mass-production capabilities, it is limited by package size, making it more suitable for larger OD modules targeting mid- to low-end TV, monitor, and vehicle markets. On the other hand, Mini COB offers the possibility of ultra-thin designs, with an OD as low as 0mm or more, but the process is more complex, with higher equipment and material requirements, resulting in lower yields. However, as technology across the industry chain matures, yield rates will improve, and Mini COB is expected to have a much broader future than Mini POB, with the potential for widespread application across all sectors. While POB packaging is primarily used in LED backlighting, it still holds a significant market share in some packaging companies and has a substantial impact on direct display packaging technologies, especially COB technology, which is why it is also discussed here.

GOB - Solving Common Issues in Traditional Surface-Mounted Packaging, such as Dead or Detached LEDs

GOB (Glue on the Board) is a specialized encapsulation method designed for LED displays, improving upon traditional SMD (Surface-Mounted Device) technology. In simple terms, it involves fixing the LED chips onto a PCB (Printed Circuit Board) and using a unique optical, thermally conductive nanomaterial to fill the gaps between the chips. This forms a tightly connected and highly protective integrated structure.

The primary advantage of GOB is its high level of protection, providing eight types of defense: waterproof, moisture-proof, shock-resistant, dustproof, corrosion-resistant, blue light protection, salt-resistant, and anti-static. Additionally, it does not negatively affect heat dissipation or result in brightness loss. Long-term testing has shown that the protective glue even helps with heat dissipation, reducing the failure rate of LEDs, enhancing the stability of the screen, and extending its lifespan.
With the application of GOB technology, the granular pixel structure originally present on the LED board surface is transformed into a smooth, flat panel, changing the display from a point light source to a surface light source. This results in more even light distribution, clearer and more transparent display effects, and significantly improves the viewing angle (up to 180° both horizontally and vertically). GOB also effectively eliminates moiré patterns, boosts contrast, reduces glare, and minimizes eye strain.
GOB technology retains the mature benefits of both SMD and COB (Chip on Board) technologies while addressing the limitations found in traditional SMD packaging. It is easy to mass-produce, ensures stable quality, and is reasonably priced, making it suitable for market demands and quick application across various industries. Before 2019, the GOB market had not been fully developed, with only a few display companies working with it. However, as the technology has matured, and with early-adopting companies pushing forward GOB small-pitch products, it has gained increasing recognition. With the rise of small-pitch LED displays in the commercial display market, user interaction has become a key demand. Traditional small-pitch LED displays need to improve surface treatments to meet touch functionality, and GOB technology, with its superior flatness, is well-suited for this. The next few years will see continued growth in GOB’s role in the small-pitch market, though as COB and MIP (Micro-LED in Package) technologies continue to advance and reduce costs, GOB’s market growth may gradually face pressure.

MIP: A New Packaging Technology for the Micro LED Era

MIP (Micro LED in Package) is a new packaging architecture based on Micro LED technology, derived from the experience of small-pitch display products. Essentially, MIP is the organic integration of Micro LED and discrete components. The method involves dividing a large area display panel into separate packages, which significantly enhances yield control in smaller areas. Additionally, by moving the testing process from the chip level to the packaging stage, MIP effectively reduces costs while increasing production speed.
From a cost perspective, MIP packaging technology does not require significant investment in new equipment and can utilize existing machinery for production. This greatly reduces the high costs associated with setting up production lines. Moreover, MIP technology moves the testing process that was traditionally done at the chip level to the packaging stage, shifting from testing the chips to pin-level testing. This not only boosts efficiency but also further drives down costs. MIP packaging also makes post-production testing and repair easier.
As different pitch products require different manufacturing processes, various packaging modes will coexist for some time. However, the trend toward shrinking pitch sizes and improving cost-effectiveness indicates that COB and MIP packaging modes have a distinct advantage. In particular, MIP is more suitable for smaller chips, allowing for a greater reduction in pitch size and further cost reduction. As Micro LED technology becomes the dominant display technology, transitioning from large-sized to small-sized applications, the chips used will continue to shrink, making the advantages of MIP even more pronounced.

LED Packaging Market Development Status

1.Overview of the LED Packaging Industry

The global LED packaging industry is primarily concentrated in regions such as Mainland China, Taiwan, Japan, South Korea, and Europe/North America. Compared to the epitaxial (or wafer) and chip industries, Mainland China’s LED packaging industry has achieved significant scale and is now on par with international technological standards. China has become a key global hub for LED packaging production.
Regionally, the Pearl River Delta is the most concentrated area for LED packaging companies in Mainland China. It is the largest industrial cluster in the country, housing numerous packaging material suppliers, equipment manufacturers, and agents, with a well-developed supporting infrastructure.

2. LED Packaging Market Recovery

In recent years, as global LED production capacity has gradually shifted, China has become the world’s most important LED production base. Supported by national industrial policies and continuous technological advancements in LED technology, China’s LED packaging market has steadily increased in value. However, in 2023, the industry experienced a downturn due to weak demand in the end markets, slow inventory digestion, and increased market price competition.
In this context, many midstream LED packaging companies saw varying degrees of negative performance. As we enter 2024, there are signs of recovery, especially in the downstream LED display and lighting markets. Several publicly listed LED packaging companies have also reported better financial results in the first half of the year.
Reviewing the first three quarters of 2024, several domestic publicly listed packaging-related companies achieved revenue and net profit growth. In terms of revenue, seven companies, including Mtc, Dongshan Precision, NationStar, JUFEI OPTOELECTRONICS, Refond Optoelectronics, and Hongli Zhihui Group, all saw revenue growth in the first three quarters. Among them, Dongshan Precision had the highest revenue, reaching 26.466 billion yuan, an increase of 17.62% year-on-year, but the contribution of its LED packaging segment to overall performance was minimal. Mtc achieved the highest growth rate, with a 27.39% increase in revenue, reaching 16.162 billion yuan.
The slow global economic recovery remains the main factor affecting the development of various industries, and the LED industry is no exception. Despite some setbacks, LED packaging companies are still on the path of continuous recovery in 2024. In the face of insufficient market demand and increasing competition, many LED packaging companies are gradually exiting the price war and are seeking business models that suit their own situations. As the future market conditions remain uncertain, LED packaging companies have recognized the key to future development.

Development Status of LED Packaging Companies and COB, MIP Module Enterprises

Currently, the TRD packaging sector in China has developed over more than 30 years, achieving a stable situation. In the application of LED display products, representative companies include: MLS (Mulinsen), NationStar, Mtc, Gaoke Huaxing, Dongshan Precision, Hongli Zhihui Group, Kinglight, Multi-Color, Xinda Optoelectronics, Ruisheng Optoelectronics, and SINYOPTO. It is important to note that vertical integration across upstream, midstream, and downstream sectors is becoming a significant trend in the LED display industry. This trend could even alter the traditional structure of the display industry in the future. Through vertical integration, midstream LED packaging companies can control key technologies across the entire supply chain, improving production efficiency and product quality while lowering costs, thus enhancing market competitiveness. At the same time, midstream packaging companies may face challenges from larger upstream and downstream players who have a several-fold advantage in size. Additionally, the entry of cross-industry capital could create further pressure. As the new display industry market grows, the competitive advantage of traditional packaging companies will weaken. In the face of significant capital, traditional packaging companies may either form strong alliances, be acquired, or rely on differentiated products to capture market share, or integrate into new industrial structures.

Mtc: Moving Toward the Strategic Goal of Becoming the "World's Largest COB Panel Manufacturer"

In 2023, Mtc Visual Display completed the construction of 900 COB production lines. By December 2023, the monthly production capacity reached 10,000 square meters. By the first half of 2024, the monthly production capacity had increased to 16,000 square meters. On July 9, 2024, during an institutional research session, Mtc announced that new production lines would be gradually brought online, with expectations that the company’s COB production capacity would exceed 20,000 square meters per month by September. In terms of industry position, according to incomplete data from institutions, Mtc Visual Display currently accounts for more than 50% of the COE industry’s shipments. With Mtc reaching 20,000 square meters in capacity by September, Mtc Visual Display will further solidify its competitiveness in the COB sector. Of course, the rapid development of Mtc Visual Display is largely due to the strong support of the Mtc Group.

It is reported that the Mtc Group has a vertical integration advantage in LED technology, with core technologies in smart display products, communication products, LED products, and other manufacturing sectors. To date, the company and its subsidiaries have been granted 1,260 valid patents, including 342 invention patents, 818 utility model patents, and 100 design patents. The company is currently applying for 770 patents and has obtained 391 software copyrights. With the help of its vertical integration advantage in LED, the cost reduction for Mtc Visual Display‘s COB products has been significant, with prices for main pitch products in 2023 dropping by 50% to two-thirds compared to the previous year.
With the vertical integration of its existing display business, Mtc will now be able to allocate and utilize resources more efficiently and rationally, further strengthening its competitiveness in the COB sector. Looking ahead, Mtc Visual Display will continue to enhance its technology R&D and market expansion, moving toward its goal of becoming the “world’s largest COB self-board manufacturer.”

NationStar Optoelectronics: MIP Covers Full-Spectrum LED Applications

In 2024, NationStar Optoelectronics will focus on advancing its MIP product series. While developing smaller pixel pitches, it will also expand into larger pitch applications, such as for rental displays, bringing a fresh understanding of MIP technology to downstream markets. To unlock the full potential of MIP applications, NationStar Optoelectronics has divided its MIP products into two main categories: MIP-IMD and MIP-CHIP, each designed to meet various LED display pitch and application requirements.

According to official information, as one of the earliest companies to enter the MIP product market, NationStar Optoelectronics’ RGB Devices Division has achieved a monthly production capacity of 1,000,000 MIP units. On the product front, the company has developed both MIP-IMD and MIP-CHIP products, covering pitch ranges from P0.6 to P2.6, and designed to meet the needs of solid installations, rental, and other applications. In particular, for the entertainment and stage performance markets, where high resolution, high contrast, and reliability are key requirements, NationStar Optoelectronics is actively promoting innovation in its MIP product line. MIP products feature a black matte package that significantly enhances display contrast. The multiple size options can accommodate various pixel pitch solutions, offering more creative possibilities. Additionally, the use of encapsulated gels ensures a wider light emission angle, chip mixing, and pre-mixed light strips, improving uniformity and consistency, which enhances the overall display effect. These products are designed to meet the diverse needs of the film and stage performance markets. Currently, NationStar Optoelectronics has developed two main MIP product lines, MIP-IMD and MIP-CHIP, with pixel pitch options ranging from P0.6 to P2.6.
It is worth noting that in mid-January 2024, NationStar Optoelectronics focused on cost reduction for its GT1010 products, achieving a price of less than ¥10,000 per square meter, making it possible to break the ¥10,000 barrier for a full P1.25 screen. Additionally, for the IMD M09, NationStar Optoelectronics plans to reduce the comprehensive cost of P0.9 to ¥20,000 per square meter in the first quarter. As NationStar Optoelectronics achieves these milestones in its MIP product development, the company continues to extend its technological applications, leading the way in the deep integration of MIP and GOB technologies. This includes launching a new MIP display panel that expands the practical application scenarios for MIP technology, empowering the development of micro-pitch displays.

Lamp Video: Micro LED COB Industrial Park Breaks 100 Million RMB in Sales Within 7 Months

According to Hunan Daily, Lamp Video’s Display Technology Industrial Park, which began operations in March this year, has achieved sales exceeding 100 million RMB in just seven months. The total investment for the Lamp Video Display Technology Industrial Park project is 1 billion RMB, with a land area of 45 acres and a construction area of over 60,000 square meters. The project is being developed in three phases.
In 2024, after the first phase of production, the facility is expected to produce 50,000 square meters of Micro LED COB display panels annually, with an estimated production value of 800 million RMB. By January 2025, the second phase will increase the production capacity to 100,000 square meters per year, with a projected production value of 1.5 billion RMB, showing significant increases in both capacity and value. After the third phase comes online in July 2025, the annual production will reach 150,000 square meters of Micro LED COB display panels, with an anticipated production value of 2 billion RMB. These products will primarily be used in large-size commercial displays, big data monitoring centers, smart meeting centers, and intelligent terminal displays, among other applications.
In recent years, Lamp Video has continued to strengthen its focus on flip-chip COB technology, driving the progress of the Mini/Micro LED industry. In 2024, the company showcased its flip-chip COB display products featuring a full flip-chip common cathode technology at various trade shows, including the 8K Black Magic large screen, the LMini 0.9 small-pitch COB dedicated display screen from the Blue Shield series, and the 54-inch Blue Magic series COB large screen.

Hi-Tech Huaye: 6 Billion RMB Investment in MLED COB Project

In December 2023, Hi-Tech Huaye’s MLED COB packaging display workshop began equipment debugging and installation. The annual output value of this COB project is expected to reach 1.3 billion RMB. The project officially started in late March 2023 with a total investment of 6 billion RMB, and is being promoted by Hi-Tech Video. The project will be built in two phases. Upon completion, the annual output value is expected to reach 10 billion RMB. According to official information, Hi-Tech Huaye was founded in 2013 and its product range includes LED light source packaging, LED displays, MLED new-type display panels, and related injection molding products. The company occupies more than 900 acres and has a production area of 350,000 square meters, making it one of the leading LED light source and LED display manufacturing bases in China.

In February 2023, Hi-Tech Huaye established Hi-Tech Video Company to focus on the research, development, production, and sales of MLED new-type display panels. The product portfolio includes modules, cabinets, and end-user products. The module products are further divided into five categories, including the standard COB module product S series and the smart COB module product W series. Currently, Hi-Tech Video has completed the development of the S series standard COB modules with pixel pitches of P0.6 to P1.2, which have been successfully applied in high-end video walls, all-in-one conference machines, and large-size TV walls.
It is understood that COB technology is increasingly in demand because it can achieve small-pitch products such as P1.0 at a lower cost, and the demand for these products is gradually increasing. Hi-Tech Huaye has been preparing for this since 2020. In 2020, the company officially launched the MLED COB new-type display panel development project. The company invested nearly 100 million RMB to build an independent laboratory and established an MLED COB flip-chip display panel research and trial production line.

Leyard Optoelectronics: Leading the Explosion of COB Technology!

As a global leader in COB (Chip-on-Board) small-pitch display technology, Leyman Optoelectronics has steadily solidified its leading position in the international market with its high-quality COB display solutions. The company is accelerating its overseas expansion of new products such as COB small-pitch large screens, smart conference all-in-one machines, and home giant screen cinemas, precisely capturing new growth points in the global market.

Particularly in the face of numerous challenges and uncertainties in the domestic market, Leyman Optoelectronics has been able to steadily grow its performance through deep expertise and continuous innovation in COB technology. This success demonstrates that technological innovation is the key force driving the company to overcome difficult times and achieve sustainable development. In October 2023, Leyman Optoelectronics pioneered the launch of PM-driven glass-based Micro LED display products, marking a significant breakthrough in the field of Micro LED display technology.
    As 2024 approaches, despite the complex and changing domestic economic environment, Leyman Optoelectronics has not slowed its pace. Instead, the company has increased its investment in COB technology R&D, with R&D expenditures growing by 8.24% compared to the previous year, demonstrating its unwavering commitment to innovation.
    Among its achievements, Leyman Optoelectronics has developed the “world’s first PM-driven glass-based Micro LED ultra-high-definition home giant screen wall.” Featuring the revolutionary TGV glass substrate and proprietary COB packaging patent technology, this product sets a new industry benchmark for ultra-high-definition visual experience and energy efficiency. The 8K Micro LED ultra-high-definition energy-efficient cold screen, relying on Leyman’s proprietary energy-saving cold screen technology and advanced COB packaging, achieves a remarkable 50% reduction in energy consumption. This product perfectly integrates the dual advantages of stunning large-screen visuals and green energy savings, leading the new generation of display technology and setting a new trend in the industry.
    To date, Leyman Optoelectronics has accumulated nearly 800 independent patents, establishing a solid patent barrier across core fields such as COB mounting, flip-chip technology, and energy-saving cold screen technology. Particularly in the field of energy-saving cold screen technology, as a domestic pioneer, Leyman Optoelectronics has been proactive in patenting, continuously applying for and securing multiple pixel arrangement structure patents, creating a comprehensive pixel engine technology system that includes pixel layout, packaging innovations, and A) algorithm optimization. Recently, several of the company’s COB energy-saving cold screen patents were officially authorized by the National Intellectual Property Administration, further consolidating Leyman Optoelectronics’ technological leadership in the industry.

HCP Technology: Continually Driving COB and MIP Cost Reduction and Efficiency Improvements

In 2019, HCP Technology became one of the first to achieve mass production of P0.7 full-package COB products. Since then, the company has made continuous breakthroughs in the field of micro-pitch LED direct display technology, further reducing pixel pitch for mass production. In June 2021, HCP‘s P0.7 products achieved a remarkable milestone with monthly orders exceeding 500 square meters. Currently, the company’s manufacturing capacity has reached 10,000 square meters per month, meeting the market’s large-scale demand for micro-pitch products.
Notably, in 2024, HCP Technology continues to focus on driving down the cost of COB technology to replace SMD (Surface Mount Device) and achieve full-domain coverage for indoor small-pitch, micro-pitch, curved, irregular LED, and virtual pixel products. Additionally, the company has introduced MIP (Mini LED Integrated Package) devices to provide differentiated product options for customers. Currently, HCP Technology‘s full flip-chip Mini COB series products have achieved full-pitch mass production from P0.4 to P1.8, while MIP products can now be produced in P0.6 and P0.9 pitches, with the MIPO404 product already launched.
Since the introduction of HCP Technology‘s full flip-chip COB products in 2019, the company has gained widespread recognition from customers due to stable quality and high industry-standard reliability. The company has established a solid reputation for its products. HCP Technology continues to adhere to a comprehensive quality management and tracking process, continuously improving quality inspection standards, and striving to provide the highest-quality products for its customers.

Hongli Display: First Launch of COB Large Module Product

Since entering the Mini/Micro LED display sector in 2018, Hongli Display, a subsidiary of Hongli Zhihui Group, has been deeply focused on the two main technology areas of Mini LED direct display and backlighting. In August 2024, Hongli Display became the first in the LED direct display industry to introduce a COB large module product with a cabinet size of 600×337.5mm. The first batch of products will cover the three main specifications: P1.25mm, P0.93mm, and P1.56mm. These three specifications account for the vast majority of global COB product sales in the market.
The 600×337.5mm COB products from Hongli Display are designed with the key feature of “lightweight and easy to use.” This not only reflects Hongli Display‘s product strategy but also aligns with the main development direction of the LED direct display market. The application of LED direct display products, especially those in the P1.0 to P1.5 range, is transitioning from high-end exclusivity to mass adoption. The competition for product adoption is not only driven by a continuous reduction in price costs but also by improvements in ease of use.
Hongli Display offers the Hongping series of Mini LED direct display products, which cover the P0.7 to P1.5 pixel pitch range. These products have already been successfully applied in home theaters, high-end conference rooms, live sports broadcasting, command centers, and commercial displays. The products feature full flip-chip COB packaging, offering smaller pitch sizes and enhanced stability.
Additionally, Hongli Display has developed its patented COB white light board solution, COB-BLU. This solution reduces costs by approximately 15%-20% compared to POB products and minimizes the use of QI film compared to Mini LED-COB backlight solutions, providing a better cost advantage. Currently, Hongli Display has completed mass production for several backlight projects, continuing to assist customers in promoting the market launch and popularization of full-size Mini LED backlight display products, enabling users to enjoy cinema-level picture quality anytime and anywhere.

TENGCAI Optoelectronics: Leading the Development of Mini COB Front and Flip Chip Modules

In April 2024, a semiconductor industry chain research and manufacturing project, with a total investment of 1 billion RMB, was signed in Ningcheng County, Chifeng, Inner Mongolia. This project is invested and constructed by Shenzhen Caiguang Electronic Display Technology Co., Ltd. According to TENGCAI Optoelectronics, the company specializes in producing and selling Mini COB front and flip-chip modules, with the goal of becoming the world’s first Mini COB module manufacturer.
In 2023, TENGCAI Optoelectronics launched a 320mm x 160mm front-mounted Mini COB module. Building on this success, in 2024, the company once again broke through technical bottlenecks and introduced a 300mm x 168.75mm front-mounted Mini COB module. This module is designed with a 16:9 golden ratio to ensure that point-to-point displays perfectly match the video sources provided by customers.

Additionally, TENGCAI Optoelectronics has introduced a Mini COB touch-screen conference all-in-one machine. This product is available in 110-inch, 135-inch, and 162-inch sizes, and can also be customized to other sizes according to specific customer needs. The product’s key features include a whiteboard writing function, 30-point infrared touch accuracy, as well as support for document management, video conferencing, and wireless screen sharing, among other functions.

Longrun Optoelectronics (LongrunLED): Ultra-High Definition Display Smart Manufacturing Base Project Plans Total Investment of 2.9 Billion RMB

On June 18, 2024, Longrun Optoelectronics officially signed and settled the Ultra-High Definition Display Smart Manufacturing Base project at the Jiangmen Jiangmu New Energy Dual-Carbon Industrial Park. The total planned investment for the project is 2.9 billion RMB, covering a land area of 249 acres. The construction will be carried out in two phases and will involve the production of Mini LED COB display screens, Micro LED direct display, Micro LED epitaxial chips, and sensor smart manufacturing production lines. Once fully operational, the project is expected to generate an annual output value exceeding 5 billion RMB.
In fact, Longrun Optoelectronics has already invested in research and development in the COB field. At this year’s ISLE exhibition, the company showcased several new products, including the CV series indoor COB ultra-high-definition LED displays and the E-PRO series outdoor COB high-brightness LED displays. Longrun Optoelectronics revealed that, in order to better provide small-pitch display solutions, the company has made significant investments in building a high-standard COB production workshop. Equipped with advanced manufacturing equipment, precise production systems, forward-thinking innovative technologies, and continually improving craft standards, Longrun Optoelectronics has introduced various new COB product solutions, supporting different installation requirements, different brightness display needs, and customized solutions for deeper demands.

AOTO Electronics: Building a 400 TMIP Display Project

Recently, the Future Stores in London, powered by AOTO Electronics, had its grand opening. This new immersive retail concept store cleverly integrates advanced display technologies with data analysis systems, seamlessly blending traditional in-store shopping experiences with innovative digital interactions, creating an unprecedented new shopping model. As the core technology partner of this project, AOTO Electronics fully supports the store’s central display area, providing robust assistance with its leading MIP series LED display solutions, covering over 400 square meters of space.

Future Stores spans over 400 square meters, with its design focusing on space flexibility and dynamic experience. AOTO Electronics provided 1,883 units of MIP1.5 series LED displays, covering a total area of over 400 square meters. These ultra-high-definition LED screens seamlessly cover the walls and ceiling of the store, creating an immersive visual environment. In addition to their exceptional display performance, these screens fully support generative AI and real-time interactivity, allowing consumers to deeply engage with brand showcases and various activities directly through the screens.

The Competition Between COB and MIP in the Micro LED Era

Since 2023, MIP packaging technology has gained significant traction in the small-pitch LED direct display market. As a new independent device packaging structure, MIP claims to perfectly inherit the “clothing stick” process chain, achieving low-cost technological advancements. Discussions about the “future” relationship between MIP and COB technologies have gradually heated up in the industry.
    Do MIP and COB have a competitive relationship? Based on the products recently launched by MIP, most of them overlap with COB’s small-pitch LED direct display products. In particular, MIP’s introduction of the surface-mount process into the ultra-small pitch market (i.e., below P1.0) has resulted in a “direct competition” relationship.
It is reported that COB technology currently holds over 50% of the market share in the P1.0 and below range. In the ultra-small pitch market, the rest of the market share is mainly occupied by “Four-in-one” (IMD, also known as MIP in one technology, a multi-in-one device). The ultra-small pitch market sees COB focusing on performance, while multi-in-one technologies emphasize cost advantages and support “surface-mount” processes. MIP technology’s application in the ultra-small pitch market is still in its early stages.
    At the same time, in recent years, COB products have seen continuous cost reduction and increasing market acceptance. The penetration rate of P1.5 products has already reached around 20%. In the future, COB products are expected to account for 30-50% of the demand in markets below P2.0. This overlaps with MIP technology, which can extend to larger pitch markets, such as P2.0 or even P3.0-P4.0.
    In addition to the overlap in pitch markets, MIP and COB face many of the same “challenges”: both technologies are considered relatively high-cost solutions. Especially in the ultra-small pitch market, while COB faces the issue of large-scale transfer, MIP is not without this challenge. However, as an independent device, MIP solves the “transfer density” issue in two steps during the creation of two-color LED chips and the final display terminal. Still, this does not address the fundamental problem of needing large quantities of devices per unit display area in ultra-small pitches.

Even though MIP uses the “surface-mount” process, MIP independent packaged devices in ultra-small pitch products are still “high-end surface-mounts,” unlike the simpler surface-mount processes seen in products like P10. For P0.5 products, whether using COB or MIP, both technologies inherently require “high-difficulty large-scale transfers.”
    Industry experts point out that the ultra-small pitch market “has no shortcuts.” With this in mind, the traditional choice for the industry has been COB as the main technology, due to its shorter production process and higher reliability of the final products. It is more suited for industry enterprises to independently develop and master high-difficulty integrated technologies. In larger pitch markets, both MIP and COB face lower manufacturing difficulty, and they will primarily compete on “cost and experience.” MIP may have more advantages in “surface-mount” technology in this regard.
    Regarding the technological relationship between MIP and COB, the industry generally believes that COB and MIP are not opposing technologies, but rather complementary. MIP is seen as “industrial substitution,” while COB is an “industrial upgrade.”
    First, considering MIP’s core advantage, its greatest significance is introducing Mini/Micro LED crystal particles into a market traditionally dominated by “surface-mount and independent RGB devices.” For products above P2.0, to integrate smaller LED crystal particles, the packaging process for RGB devices must be adapted to the new miniaturized LED crystal particles and epitaxy technologies.
    The result of this improvement is MIP. Based on Mini/Micro LED technology, MIP replaces part of the traditional RGB LED products. This is a necessary step in the context of continuous upgrades in LED product light efficiency, which COB technology cannot achieve.
    Second, the core advantage of COB products, in addition to reliability, durability, and display performance, also includes advantages in the “industrial process.” For LED displays, COB is not just a packaging technology but also a terminal forming technology. From the epitaxial wafer to the final terminal cell, COB handles the entire process.
    This has huge benefits in the era of micro-pitch and smaller pitches, helping to shorten the “manufacturing chain” and enhance the “technical concentration” of mid-to-high-end products. COB products represent both an advancement in user experience and a reintegration of the supply chain, assisting with the upgrade of pitch indicators. Their industry characteristics make them key players in “paving new markets for small-pitch LED displays.”
    On the other hand, the further development of both MIP and COB technologies requires solving shared upstream and midstream issues such as “large-scale transfer,” “Micro LED crystal quality and consistency,” and “ultra-fine structure repair.” In fact, many industry experts view MIP as a form of single RGB packaging technology for COB, similar to how multi-in-one technologies like IMD were once considered to be just a type of COB technology. Many industry enterprises have started to lay out both MIP and COB technologies. On the one hand, companies with successful COB technology capabilities will not give up their advantages and early investments. However, MIP’s potential to replace traditional RGB LED products above P1.0 and introduce Mini LED or even Micro LED into the market means that companies must keep track of the development of MIP technology. In the ultra-small pitch market, the selection differences of customers will inevitably give MIP a feasible market space.
    On the other hand, for companies that have not yet entered the ultra-small pitch LED market or do not possess COB technology capabilities, following MIP technology is their only viable route into the Mini/Micro era. Their enthusiasm for investment depends on MIP’s competitiveness in traditional pitch markets, especially regarding its cost advantage.
    According to most industry experts, one of the main risks in the LED direct display industry is “innovation iteration happening too quickly.” In this context, if companies choose the wrong side, there may be very little time for “changing lanes.” For leading enterprises, pursuing multiple technological routes simultaneously is considered a “better, balanced choice.”

MIP is expected to accelerate the popularization of Micro LED applications, which has already had a significant impact on the industry! Experts in the field point out that the large-scale price reduction of COB products from the second half of 2023 to mid-2024, with prices halving and sales doubling, is largely intended to ensure that COB technology does not fall behind MIP in market development.
However, the reality is that most COB products currently use Mini LED chips, and only a small number of COB products use Micro LED chips. Very few COB products use MIP packaging devices: some MIP-packaged LED direct display screens use COB-like surface coating processes. COB and MIP have already formed a comprehensive competition around cost competitiveness, form, reliability, durability, and other dimensions of terminal packaging structure.
In mid-2023, COB product prices significantly dropped, to some extent hindering the rapid deployment of MIP. Currently, MIP technology products, in the P1.2 and below pitch range, are still not significantly cheaper than COB products. However, MIP is widely applicable in markets with a P1.5 or above pitch.
But in larger-pitch markets, MIP must also face “cost competition” from traditional SMD surface-mount devices. Theoretically, MIP has better black area coverage and lower LED chip material costs than SMD at the same pitch. However, this requires a series of integrated processes and industry scale support to become a truly competitive market force.
From a cost perspective, COB’s drastic price reduction, along with the already mature and low-priced SMD products, poses the main competitive pressure for MIP. Especially after MIP adopts COB-like surface processing technology, its cost currently does not have any significant advantages. However, like any new technology, MIP will undergo a cost reduction process, and in the future, as costs continue to decrease, the industry’s competitive landscape will change dramatically.
Apart from the opposition between COB and MIP, a significant portion of the industry believes that MIP’s main battlefield lies in P1.0 and below, and that MIP and COB will coexist in the future, with each technology being selected for different application scenarios. There is no clear “replacement” of one by the other. MIP is a breakthrough in the industry, but who can guarantee that COB will not make further breakthroughs in the future? At the same time, the attitudes of different industry chain segments towards these two technologies, and the different capabilities and interests of enterprises in these technologies, will determine the overall market layout of these two technologies. In the short term, MIP and COB will be “two essential legs for industry progress.”

Challenges and Difficulties in the LED Packaging Industry

Challenges in LED Packaging and Yield Issues
With the advancement of LED technology, the complexity of packaging has been increasing, and yield rates are becoming a growing concern. This issue is especially prominent in the fields of Mini LED and Micro LED. Due to the tiny chip sizes and large quantities, even the smallest error during the packaging process can lead to product failure, severely impacting yield rates. In the cutting-edge domains of Mini LED and Micro LED display technology, packaging difficulty and yield issues are especially critical. The chips are extremely small, and their quantity is vast, requiring precision and stability during the packaging process. Furthermore, the broad range of applications for Mini LED and Micro LED demands exceptional performance from the final product. This makes any slight error during the packaging process capable of causing product failure, severely affecting yield rates.
To enhance the yield rates of Mini LED/Micro LED products, businesses and research institutions in the industry are continuously exploring new packaging technologies and methods. COB (Chip On Board) and MIP (Massive Integrated Packaging) are becoming two primary approaches for the micro-pitch LED display era. Companies are using advanced packaging equipment and technologies, optimizing packaging processes, and improving testing and screening precision. Additionally, enhancing collaboration across the entire supply chain is key to improving overall production efficiency and yield rates. Moreover, selecting appropriate materials is crucial for the packaging process. Packaging materials need to exhibit excellent electrical properties, thermal stability, and mechanical strength to ensure that the final products have reliability and durability. As such, LED packaging companies and research institutions continue to explore new materials and technologies to improve packaging performance and yield rates.

Intensified Competition in the LED Packaging Market and the Risk of Overcapacity in COB
In recent years, as LED technology has advanced and its application areas continue to expand, COB (Chip On Board) packaging technology has gained significant attention in the industry due to its unique advantages. However, with the lowering of technological barriers and the active entry of leading manufacturers, competition in the COB market has become increasingly intense, and the risk of overcapacity is emerging.
COB packaging technology directly dissipates heat via the substrate, reducing the manufacturing complexity and cost of the mounting bracket while lowering thermal resistance and improving heat dissipation performance. As technology matures and improves, the difficulty of COB packaging decreases, and technological barriers are lowered, allowing more companies to enter the field, intensifying market competition. Many brands with strong R&D capabilities and market influence are establishing themselves in this area. These companies improve their competitiveness in the COB market by introducing advanced equipment, optimizing processes, and enhancing product quality. They are also expanding into new application areas, making the market even more competitive and increasing the risk of overcapacity.

Overcapacity not only leads to issues like inventory backlogs and financial strain but also negatively impacts the entire LED industry. First, overcapacity intensifies market competition, leading to price wars that squeeze profit margins. Secondly, overcapacity leads to resource wastage and worsens environmental pollution. Lastly, it affects the sustainability of the entire industry’s development.

Cost Pressure in LED Packaging for Mini/Micro LEDs
LED packaging, a critical step in semiconductor manufacturing, plays an essential role in the development of Mini/Micro LEDs. However, as technology progresses and market competition intensifies, LED packaging in the Mini/Micro LED sector faces unprecedented cost pressures.
For Mini LEDs, the packaging process must address challenges such as heat dissipation, optical design, and electrical connections. To achieve high brightness, Mini LEDs often use flip-chip structures, which increases both packaging difficulty and cost. Additionally, due to the small chip size, high precision in positioning and soldering is required to ensure each chip functions accurately and reliably. These technical requirements not only increase production costs but also limit the mass production capacity and yield of Mini LEDs.

The challenges are even more severe for Micro LEDs. Given the extremely small size of the chips, packaging requires large-scale chip transfer and precise alignment, demanding packaging equipment with high accuracy and stability. Furthermore, packaging for Micro LEDs must address challenges such as integrating driver circuits, wafer-level packaging, and maintenance. These technical bottlenecks raise packaging costs and hinder the commercialization process of Micro LEDs.

Market competition is also a significant factor contributing to cost pressure in LED packaging for Mini/Micro LEDs. With an increasing number of companies entering the market, competition has become fierce. To secure market share, companies are often forced to reduce product prices, striving for better cost-effectiveness. However, this often results in sacrificing product quality and profit margins. In the face of such intense competition, businesses must increase R&D investment, improve production efficiency, and lower production costs. However, these efforts often cannot fully offset the pressure from price reductions, leading to shrinking profit margins in LED packaging for Mini/Micro LEDs.

Optimizing and upgrading production processes is key to reducing costs in the LED packaging sector for Mini/Micro LEDs. However, process optimization requires substantial R&D investments and time costs. Furthermore, process improvements must be coordinated with chip design, packaging materials, driver ICs, and other elements to ensure the efficiency and smooth flow of the entire production process. These requirements not only increase the complexity of production but also raise costs.

Future Trends in LED Packaging Technology

As an integral part of semiconductor display technology, LED packaging has demonstrated robust development in recent years across various sectors. With continuous technological advancements and the expansion of emerging application markets, the future of LED packaging technology is showing several promising trends.

Technological Advancements
LED packaging technology is continually advancing toward miniaturization, integration, and precision. Traditional LED packaging methods can no longer meet the market demand for high resolution, high brightness, and low power consumption. As a result, new packaging technologies such as COB and MIP have emerged. These technologies not only improve the performance and quality of LED products but also reduce production costs, enabling broader applications in lighting, display, and backlighting industries. In particular, the rapid development of Mini LED and Micro LED technologies has significantly improved key performance indicators like resolution, brightness, and contrast for LED displays, offering strong support for applications in high-definition displays, virtual reality, and augmented reality.

Expanding Market Demand
The application areas for LED packaging products continue to broaden, and market penetration is steadily increasing. In the display sector, LED displays are becoming increasingly common in advertising, shopping malls, sports venues, and performance stages. With technological advancements and decreasing costs, LED displays are also entering new fields such as home theaters and virtual production. Additionally, LED packaging products are showing enormous potential in industries like automotive, healthcare, and security, providing strong support for the transformation and upgrading of these sectors.

Changing Market Dynamics
The competitive landscape of the LED packaging industry is evolving. As technology progresses and economies of scale come into play, the barriers to entry are gradually increasing, and market concentration is on the rise. Companies with core technologies and market advantages are likely to emerge as industry leaders. Meanwhile, as new application markets expand, LED packaging companies will need to continuously innovate to meet diverse market demands. This will require companies to have strong R&D capabilities, keen market insights, and the ability to rapidly respond to market changes.

Looking ahead, the LED packaging industry will face more intense competition, but also more market opportunities and growth points. Several key trends are expected to shape its future:

The rapid development of Mini LED and Micro LED technologies, which have high display quality and low power consumption. As production scales up and yield rates improve, costs are expected to decrease, making these technologies viable for consumer electronics, automotive, and other markets.
The widespread application of smart LED technology. By integrating the Internet of Things (IoT), big data, and other technologies, LED products can be intelligently controlled and managed, presenting new development opportunities for the LED packaging industry.
Environmental sustainability and eco-friendly practices are becoming industry standards. With stricter environmental regulations and growing consumer demand for eco-friendly products, LED packaging companies will need to adopt sustainable materials and processes to ensure long-term viability.
However, there are also challenges ahead, including:

Insufficient innovation capabilities in certain core technologies, which are still dominated by foreign companies. More investment in R&D and innovation is needed to enhance the core competitiveness of domestic LED packaging firms.
The price war phenomenon, which can negatively affect the healthy development of the industry. There is a need to standardize market practices and promote self-regulation to foster a healthy, orderly industry.
Technical barriers and market entry obstacles in some application areas, which hinder the promotion and adoption of LED products. Increased market expansion efforts are needed to drive the development of LED packaging products in emerging sectors.

Conclusion

In the LED industry chain, the packaging segment plays a crucial role as the bridge between upstream chip manufacturing and downstream application markets. Over the past few years, with the continuous maturation of LED technology and the expanding range of applications, midstream LED packaging companies have begun to actively cross into the downstream LED display market. This trend has not only promoted deeper integration within the industry chain but has also injected new vitality into the transformation and upgrading of the LED industry. However, LED packaging companies’ vertical entry into the downstream display market also faces several challenges. This has undoubtedly intensified competition in the downstream LED display market, which is evident not only in terms of price but also in product quality, technological advancements, and after-sales service.

Additionally, the domestic LED packaging industry has formed a complete industrial chain, with specialized companies engaged in every segment, from upstream chip manufacturing to downstream applications. Particularly in the Pearl River Delta region, a large number of LED packaging companies have gathered, forming a massive industrial cluster. These companies possess strong capabilities and advantages in areas such as R&D, production, and market sales, providing strong support for the rapid development of the LED packaging industry.

It is worth noting that the LED packaging industry is currently undergoing rapid development and transformation. New characteristics and trends are emerging in terms of technological applications, market demand, and competition. Looking ahead, with continued technological advancements and the expanding market, the LED packaging industry will face more development opportunities and challenges.

However, in the face of market competition and technological changes, LED packaging companies must maintain sharp market insights and continuous technological innovation to meet the ever-changing market demands and trends. At the same time, it is essential to invest in brand building, channel expansion, and after-sales services to enhance overall competitiveness and market position. Only by doing so can companies stay competitive in the fiercely contested market and achieve sustainable development.