Concerned about surprises Label: Ceramic package substrate for high power LED package Previous: Spring classification and utility analysis Next: Several conveyor belt joint methods Mdf Tite Screws,Screws For Mdf Wood,Mdf Screws Menards,Mdf Board Fasteners NINGBO YWC IMP. & EXP. CO.,LTD , https://www.nbywc-fastener.com
The heating of white LEDs increases with the increase of input current intensity, which will cause the temperature rise effect of LED chips, resulting in a decrease in light output. Therefore, the selection of LED package structure and materials is very important. In the past, LEDs often used low thermal conductivity resin packages, which became one of the reasons that affect the heat dissipation characteristics of LEDs. However, in recent years, high thermal conductivity ceramics or resin packaging structures with metal plates have been gradually used. At present, high-power LED chips often increase the luminous intensity by increasing the size of the LED chip, improving the luminous efficiency of the LED chip, using a high light-efficiency efficiency package, and a large current. The conventional resin package cannot meet the demanding heat dissipation requirements.
In the past, the traditional high heat dissipation package was to place the LED chip on the metal substrate and then coated with the resin. However, the metal thermal expansion coefficient of the package was quite different from that of the LED chip. When the temperature changes greatly or the package operation is not easy, the package operation is very easy. Thermal skew is generated, which in turn causes chip defects or reduced luminous efficiency. The ceramic package substrate can effectively solve the thermal skew problem. This is mainly because the ceramic material for LED packaging is divided into aluminum oxide and aluminum nitride. The thermal conductivity of aluminum oxide is 55 times that of epoxy resin, and aluminum nitride is 400 times that of epoxy resin. Therefore, the substrate for high-power LED packaging is currently used. Aluminum having a thermal conductivity of 200 W/mK or a copper metal package substrate having a thermal conductivity of 400 W/mK is often used.
We all know that in addition to protecting the internal LED chip, the LED package has the functions of electrically connecting the LED chip to the outside and dissipating heat. The LED package requires that the light generated by the LED chip can be efficiently transmitted to the outside. Therefore, the package must have high strength, high insulation, high thermal conductivity and high reflectivity. It is exciting that the ceramic package has almost all of the above characteristics, and then ceramics. Heat resistance and light deterioration resistance are also superior to resins.
In the future, when developing high-power LED chips, it will inevitably face the problem of thermal skew. This is a problem that cannot be ignored. The packaging structure of high-power LEDs not only requires micro-wiring technology capable of supporting epitaxial bonding of LED chips, but also regarding the development of materials, although aluminum nitride has high thermal conductivity, the interaction between high heat conduction and reflectivity has become a new problem. . If the LED thermal conductivity of aluminum nitride can be improved in the future and the LED chip is close to the thermal expansion coefficient of the ceramic, the problem of thermal skew of the high-power LED is solved. 
In the high input field, the irradiance is saturated and attenuated. This phenomenon is mainly caused by the heat generated by the LED chip. Therefore, when manufacturing a high-power LED chip, the heat dissipation problem must be solved first.