China's LED industry needs to break through the bottleneck of packaging

In recent years, the LED industry began to calm down from the bright lighting revolution, and China's LED industry has become increasingly mature and rational. The luminous efficacy of light-emitting diodes (LEDs) has also increased significantly in the past decade. From the past 20 lumens per watt to the recent 150 lumens per watt, the current high-power LEDs have reached the point where they are suitable for large-scale general-purpose semiconductor lighting. And semiconductor lighting has such major advantages as energy saving, environmental protection, long-term, etc., is a new generation of lighting sources worthy of promotion, and LED packaging is the key technology to achieve the above performance, it is also the key point for China's LED industry to urgently need to break through.

A few days ago, the reporter learned from the creative era of the organizer of the Electronic Fair of the Hi-tech Fair that in order to help local LED lighting companies to seek breakthroughs in key technologies, they have overcome the technical gap with Western companies in the lighting revolution, at the Twelfth Hi-tech Fair Electronics Show. During the period of (ELEXCON2010), the era of creativity will invite Prof. Li Shijun from Hong Kong University of Science and Technology to sit in the "High-Brightness LED Packaging Workshop" to answer questions for participants, introduce the evolution and development trend of lighting sources, and elaborate on the LED packaging structure. The scope of the lecture includes the interconnection technology of the chip, the coating of the phosphor, the manufacturing process of the plastic package, and the heat-dissipation material and thermal management; the technical problems of the optical design, optical analysis, and optical detection of the LED will also be described in detail. In addition, this workshop will also discuss the application of high-brightness LED arrays and modules in general and special lighting projects, and analyze relevant cases. At the end of the course, we will introduce the outlook and technology roadmap for semiconductor lighting and discuss issues related to patents.

The LED industry chain is generally divided into upper, middle and lower reaches, which are LED epitaxial chips, LED packages and LED applications. As the LED packaging industry in the LED industry chain, it plays an unparalleled role in the entire industry chain. In the field of LED lighting, where the industry is widely concerned, the progress of packaging technology is particularly important. The difference in packaging technology can directly affect the quality of LED products. A good package and heat dissipation technology can make the LED work below the junction temperature of 60°C, and the lifetime can exceed 50,000 hours. The poor packaging technology will shorten the LED life by more than half.

According to the research agency iSuppli, the compound annual growth rate of global LED market sales will be approximately 14.6% from 2006 to 2012. The application of emerging large-area LCD backlights, automotive lighting and general lighting will stimulate LED growth. It is estimated that by 2012, the LED market will reach US$ 12.3 billion. The improvement of the efficiency of the current chip enables the efficiency of some high-efficiency LED street lamps to reach 80 lm/W or more, which has the advantage of energy saving, and its reliability and service life need to rely on the packaging technology to further improve.

LED packaging technology is mostly based on the development and evolution of discrete device packaging technology, but it has a lot of special features. Under normal circumstances, the die of the discrete device is sealed in the package body, the role of the package is mainly to protect the die and complete the electrical interconnection. The LED package is to complete the output of electrical signals, to protect the normal work of the die, the output: the function of visible light, both electrical parameters, and optical parameters of the design and technical requirements, can not simply use discrete device packaging for LED.

At present, the reasons for restricting the development of China's LED packaging industry, from the technical point of view: First, the key packaging raw materials: such as substrate materials, organic plastic (silica gel, epoxy resin), phosphors and other properties to be improved. Second, the heat dissipation of high-power LED packaging technology has not yet been completely resolved. Third, the packaging structure should be innovative for different applications. These technical problems need to be continuously improved and overcome. When epitaxial chip technology is improved, the cost of the chip rapidly declines. However, the discrete chip backend process and traditional packaging process become the bottleneck of the system cost. In fact, the gold content of packaging technology is no less than that of chip production. How to solve the problem of LED heat dissipation? How to reduce the thermal resistance of the LED? How to increase the LED light output efficiency? How to increase the reliability of LED? These problems will be discussed in the high-brightness LED packaging workshops. The companies and engineers who are interested can still visit the official website of the Electronic Fair of the High-Tech Fair or the Liaison Group. Committee registration, access to face-to-face exchange opportunities with LED packaging masters.

At present, LED companies face great opportunities: a good policy environment, strong market demand and broad space for development, as long as they can overcome the challenges from technological innovation, standardization, intellectual property rights, and economies of scale, and build first-class international and domestic leading scales. Packaging companies will no longer be dreams!