LED的COB封装热仿真设计

通过对COB封装中常用的陶瓷基板和金属基板这两类不同的基板材料进行有限元热仿真模拟,获得各自芯片到基板的仿真热阻,再使用红外热成像仪得到两种基板各自的表面温度分布情况并计算出实际热阻。仿真热阻与实际热阻的一致性表明了所采用的仿真计算方法的可用性。利用有限元仿真对COB封装的热管理方案进行了优化分析。研究表明:相对于金属基板,陶瓷基板由于无绝缘层这一散热瓶颈,其芯片到基板的热阻值约为金属基板封装方案的1/2;而且陶瓷基板有着更大的热管理优化空间,能更好地满足大功率LED封装的散热需要。

Thermal Simulation for Design of LED COB Package

Two typical types of substrate materials,i.e.,ceramic substrates without insulating layer and metal substrate with insulating layer were studied for the thermal management of COB package.Their chip-to-substrate thermal resistances were simulated and calculated by finite element method.Temperature distribution in two substrates was obtained by infrared thermography,which confirmed the adopted finite element method is feasible in our experiment.Based on these studies,the thermal management of COB package was optimized by finite element simulation.The results show that the ceramic substrate has a lower chip-to-substrate thermal resistance(only half of that of the metal substrate),which indicate that it is more suitable for the heat dissipation in high-power LED package.