LED solid-state lighting has high efficiency, long lives, flexible application, non-polluting and more advantages. It has been widely applied in the field of lighting.
In recent years, withing LED industry rapid development, market compete more and more intensely. The trend of competitive companies is move up to value chain, enhance automotive lights, plants lamp, smart lamp, Mini/MircoLED new style monitor innovation research and development on segmentation, focus on LED industry emerging fields.
Also automotive being lighting segments with high attention in the industry. Many automotive companies have been gradually increase replaced with traditional car lamp, the marketing of car lamps was turn on LED industry more and more obvious. But facing car lamp fever problem has always been tricky.
High power LED’s wafer power density is very huge, because the reason of semiconductor manufacturing technology, more than 80% input power convert to heat power, only less than 20% convert to light power. When temperature raises LED chromaticity will be deteriorates, LED is cold light, mainly heat dissipation is heat conduction. Therefore, heat dissipation is very significant for heat dissipation.
Solving LED lamps heat dissipation, start with two main aspects, before and after packaging, can understood LED wafer and lamps heat dissipation. Because any LED will be making lamps, so LED wafer always dispersed into the air through the housing of the lamps behind produced heat. If heat dissipation not good and long time working in a high temperature state. It’ll life shorten soon. Because LED wafer heat capacity were very small, a little bit heats accumulation will let wafer’s junction temperature rises rapidly. However, there are many ways for this heat actually guide wafer to outside air. Specifically, LED wafer making heat were from metal heat sink, cross solder first to PCB aluminum plate, and then cross thermal adhesive to aluminum radiator. So LED wafer heat dissipation are actually including conduct and dissipation heat two part. Then, thermal adhesive is very important to LED lamps dissipation.
Thermal adhesive is a heat medium, using silicone to basic raw material, increase various sub-materials, thought special processes. A kind of lipid-like polymer composite material synthesized by special process. It’s a thermally conductive insulating viscous object. Normally situation, thermal adhesive is not soluble in water and not easily oxidized, also has a certain lubricity and electrical insulation. The chemical and physical properties are stable and have excellent thermal conductivity, electrical insulation, high temperature resistance, aging resistance and waterproof properties.
Due to the uneven surface of the components and metal devices, when the LED chip substrate and the heat sink are in direct contact, there is a large gap, and the thermal resistance is greatly improved, which greatly reduces the heat dissipation efficiency of the heat sink. Thermal adhesive thickness and hardness degree could according to design’s different make adjustments, therefore thermal silicone sheet can fully enlarge LED wafer substrate and radiator effective contact area, reducing radiators produce costs.
To sum up, the reasonable selection of thermal interface materials such as thermal conductive glue can greatly improve the service life of LED lamps, effectively reduce the production cost of LED lamps, and greatly enhance the competitiveness of enterprise.