Now commonly referred to as the substrate for the LED substrate "LED cooling substrate " It is actually derived out from the conventional printed circuit board (PCB) . Despite there is on common between them, but because of differences in applications, it is with conventional PCB in product performance, technological processing conditions, and even differ in terms of product structure, in particular, more prominent substrate LED its thermal conductivity, heat and other characteristics. The heat from chip conduction through the heat path to the heat sink, heat sink to radiate through the air convection or heat. In the high-power LED cooling channel, cooling the substrate channel connecting the key internal and external cooling, at least the following three functions:

1.  LED chips heat clearance; 
2.  LDE chip electrical connections; 
3.  LED chip physical support. 

Most of the various structures can not do without heat LED package substrate, it has become an important component of LDE one package.
Figure 2 shows the thermal substrate position in the LED package, from which we can further understand its function in the LED package and effect. With the popularity of high-power LED, it has become the mainstream of the development of varieties of LED. The future will be toward the higher brightness LED (ie power) direction. This makes the cooling performance of cooling the substrate to widow becoming more prominent. Directly affects the heat dissipation LED device light output characteristics and the life of high-power LED package is the key issue. Cooling the substrate is white LED lighting system inside and outside the thermal pathway that connects the core components related to the multi-chip LED package structure and layout; LED outside the package reliability. LED electrical connections throughout the system, physical support, thermal characteristics, package process and cost, to a large extent depends on the cooling substrate with different structure, performance and quality.