The electrode of LED chip on silicon carbide substrate (CREE Company of the United States uses SiC material as the substrate) is an L-shaped electrode, and the current flows longitudinally. The device made of this substrate has very good electrical conductivity and thermal conductivity, which is beneficial to the manufacture of large-area high-power devices.

The thermal conductivity of silicon carbide substrate (the thermal conductivity of silicon carbide is 490 W/(m k)) is 10 times that of sapphire substrate. Sapphire itself is a poor conductor of heat, and the bottom of the device needs to be fixed with silver glue, which has poor heat transfer performance. The chip electrode using silicon carbide substrate is L-shaped, and the two electrodes are distributed on the surface and bottom of the device, and the generated heat can be directly led out through the electrodes; At the same time, this substrate does not need a current diffusion layer, so the light will not be absorbed by the material of the current diffusion layer, and the light extraction efficiency is improved. However, compared with sapphire substrate, the manufacturing cost of silicon carbide is higher, and the corresponding cost needs to be reduced to realize its commercialization.