What are the packaging technologies of automobile LED chips

LED bulb market share in the automotive lighting industry is growing. With the large-scale use of LED products, the production technology of LED bulb is also constantly improving. The existing market has higher and higher requirements for led enterprises. LED chip is very important in LED bulb. The high requirements of the market for LED bulbs will also be reflected in the production technology of LED chips. At present, the packaging of LED chips in the market is mainly divided into six categories.

1. Cob integrated package

COB（chip on  Board) packaging bulb occupies nearly 40% of the market of LED bulb. Cob packaging is to directly adhere the exposed chip on the circuit board. The obvious advantages are simple circuit design, low cost, space saving, and the technology of cob packaging is mature. But the obvious disadvantage of cob packaging is that the chip is directly exposed to the outside, vulnerable to external environment and human pollution, and cob packaging There is a fatal drawback: astigmatism. Now, the use of cob has not been more than a few years ago.

2. AC LED package

AC LED packaging, integration of more components, the composition of the chip, improve the brightness of the chip, create a simple application of micro engine. By reducing the voltage difference between the input and output voltage, improving the working efficiency of the LED driving power supply and reducing the heat dissipation requirements of the LED bulb, not only the cost of the driving power is saved, but also the service life of the LED bulb is improved. However, the fatal disadvantage of the high-voltage package is the high requirements for the radiator, which will significantly increase the cost of the radiator. It can be said that led chip packaging is a major trend.

3. Led EMC package

EMC technology is the technology of packaging integrated circuit with insulating plastic or ceramic materials, which has the advantages of high heat resistance, UV resistance, high integration, high current, small volume, high stability and so on. However, in the process of EMC packaging, there are many problems such as unfilled packaging, uneven filling, porosity and edge cracking. Therefore, in the process of packaging, the technical operation requirements are very high.

4. Flip LED technology

With the advantages of high density and high current, flip LED has become the research hotspot of LED chip enterprises and the mainstream direction of LED industry development in recent two years. At present, CSP packaging is based on flip technology. Compared with the formal installation, the flip led eliminates the link of gold wire, reduces the dead foam rate, ensures the stability of the product, and improves the heat dissipation ability of the product itself. At the same time, it can withstand larger current drive on smaller chip area, obtain higher luminous flux and thinness. It is the best solution of super current drive in lighting and backlight applications.

Although flip LED technology is gradually sought after by the industry, there are still many difficulties in the popularization of flip LED technology. Flip chip technology requires high equipment, complex process, high operation difficulty, high cost, high loss of finished products and low luminous flux. Therefore, the popularity of flip chip LED technology may need a period of development.

5. RP packaging technology

Remote fluorescent packaging technology, fluorescent powder non-contact packaging technology, packaging technology is simple, conducive to heat dissipation, prolong the service life of LED, uniform light, LED color temperature, color adjustable, low cost. But at present, the progress is relatively slow, and few enterprises invest in R & D.

6. CSP chip level packaging

CSP (chip scale package) packaging technology can be said to be the most popular LED chip level packaging technology. CSP packaging has the advantages of small size, light weight, thin chip, good heat dissipation, multiple input and output terminals. At present, CSP is gradually being used in mobile flash, display backlight and other fields.
 

CSP packaging process flow, process requirements, high cost. At present, although CSP chip level packaging is also mass produced in China, it has not been popularized. With the continuous application and improvement of CSP technology, the cost performance of CSP technology will be further improved, and more and more CSP products will be used in the next year or two.