The main problems of high-power COB packaging

8 views admin 2025-01-16

After a period of silence, COB technology is now gradually being used by many manufacturers for LED packaging, but there are still some problems that need to be solved:

The heat dissipation of COB is related to many factors, among which the heat dissipation performance of the substrate plays a key role in the heat dissipation of the entire packaging system. At present, there are two main types of substrates used in COB, aluminum substrates and ceramic substrates. Among them, aluminum substrates are relatively cheap and have poor heat dissipation performance, while ceramic substrates are more expensive and have better heat dissipation performance. In addition to heat dissipation performance, these two substrates also have some other performance differences. Therefore, packaging companies need to consider many factors when choosing these two substrates.

Packaging glue has a great impact on COB packaging and other LED packaging forms. At present, silicone with better performance has gradually replaced the epoxy resin glue used by most packaging manufacturers, especially for high-power LED packaging. Silicone resin has become the first choice of many packaging manufacturers. However, there are many types of silicone on the market, and the performance and price are also very different. For packaging companies, there are many factors to consider when choosing a packaging glue that suits them.

In the COB packaging process, the choice of chip is crucial. The chip is not only related to the light effect of the entire LED, but also has a great relationship with heat dissipation. In the selection of chips, many companies and even researchers have not fully considered the matching of chips with phosphors, packaging glue, and the matching of chips with substrates.

There are many kinds of heat dissipation structures that can be used for COB packaging, but the designs of these heat dissipation structures are improved based on the heat dissipation structure originally proposed. There are still many problems to be solved in the actual production of using these heat dissipation structures, such as whether the heat dissipation performance of the structure can achieve the expected effect, the complexity of the heat dissipation structure processing, whether the manufacturing cost of the heat dissipation structure is consistent with the customer's acceptance, etc. Packaging companies need to consider these issues in actual production.

05 Suggestions and prospects In response to the above-mentioned COB problems, the following solutions are proposed:

1. Substrate selection. Companies should choose the substrate used in production according to the selected packaged chips and product positioning. Different chips need to be matched with different substrates to achieve better heat dissipation effects. The best practice is to customize the substrate according to the type of chip and the heat generation. From the current application situation and research progress of enterprises, ceramic substrates have better performance than aluminum substrates. If the enterprise is positioned as a high-end product, ceramic substrates can be selected. In addition, some new substrates have appeared on the market, such as copper substrates, mirror aluminum substrates and silver-plated aluminum substrates. These types of substrates can also be used for packaging.

2. For the selection of encapsulation glue, first of all, market research should be conducted to fully understand the performance and price differences of encapsulation glue on the market. This is crucial for the final selection of the type of encapsulation glue. In addition, experiments should be conducted on the purchased encapsulation glue to facilitate the packaging company to better understand the properties of the glue to be used. Especially for some relatively low-priced glues, experiments should be conducted to fully evaluate their performance. In addition, experiments should be conducted on different batches of glue to determine the best conditions for use.

3. For the selection of chips, due to the wide variety of high-power chips on the market, there are certain difficulties in selection. This requires researchers to fully evaluate the performance of chips on the basis of fully understanding the matching of chips with phosphors, encapsulation glue and substrates. In practice, it is necessary to conduct experiments on the chips to be used, and compare whether the chips can achieve the required light efficiency and heat dissipation performance in matching with phosphors, encapsulation glue and substrates. After comprehensive evaluation, it is determined that the final chip used can achieve the best effect.

4. If the company has a high-level research team, it can try to study the special heat dissipation structure and apply for a patent. This can not only prevent others from imitating, but also increase the competitive advantage of its own products. If the company wants to reduce costs, it can consider using traditional packaging structures and choosing suitable materials, which can also ensure the quality of the product.

In recent years, COB packaging, especially high-power COB packaging, has made great progress, and the product has also occupied a certain share in the market. As long as companies continue to improve product performance in actual production, the performance of COB products will definitely be greatly improved, and the application range of products will be expanded faster.