Currently used for LED substrate substrates are generally called "LED heat dissipation substrates". It is actually derived from the conventional printed circuit board (PCB). Although there are commonalities between them, due to the difference in application fields, it is different from conventional PCBs in terms of product performance, process conditions, and even product structure. In particular, LED heat dissipation substrates highlight its heat conduction and heat resistance. And other characteristics. The heat of the chip is conducted to the heat sink through the internal heat path, and the heat sink dissipates heat through air convection or outward radiation. In the high-power LED heat dissipation channel, the heat dissipation substrate is the key link connecting the internal and external heat dissipation channels, and has at least the following three functions:

　?、?The heat dissipation clearance of LED chips;

　?、?The electrical connection of the LDE chip;

　?、?Physical support for LED chips. Most of the LED packages of various structures are inseparable from the heat dissipation substrate, which has become one of the important components of the LDE package.

Figure 2 shows the position of the heat sink substrate in the LED package, from which we can further understand its function and role in the LED package.

With the popularity of high-power LEDs, it has become the mainstream variety of LED development. In the future, LEDs will develop in the direction of higher brightness (ie, high power). This makes the heat dissipation performance of the heat dissipation substrate more and more outstanding.

The heat dissipation problem directly affects the light output characteristics of the LED and the life of the device, and is a key issue in high-power LED packaging. The heat dissipation substrate is the core component of the LED white light lighting system that connects the internal and external thermal pathways, and is related to the structure and layout of the multi-chip LED package; the reliability of the LED external package. The electrical connection, physical support, heat dissipation characteristics, packaging process and cost of the entire LED system vary greatly depending on the structure, performance, and quality of the heat dissipation substrate.