基于共晶焊接工艺和板上封装技术的大功率LED热特性分析

采用ANSYS有限元热分析软件,模拟了基于共晶焊接工艺和板上封装技术的大功率LED器件,并对比分析了COB封装器件与传统分立器件、共晶焊工艺与固晶胶粘接工艺的散热性能。结果表明:采用COB封装结构和共晶焊接工艺能获得更低热阻的LED灯具;芯片温度随芯片间距的减小而增大;固晶层厚度增大,芯片温度增大,而最大热应力减小。同时采用COB封装方式和共晶焊接工艺,并优化芯片间距和固晶层厚度,能有效改善大功率LED的热特性。

Thermal Analysis of High power LED Based on Eutectic Welding Process and COB Packaging Technology

High power LED devices based on eutectic welding process and COB packaging technology were simulated by using ANSYS finite element analysis software. The thermal performance of COB packaging device and traditional discrete device, as well as eutectic welding process and adhesive bonding process, were contrastively analyzed. Simulations indicate that, the thermal resistance can be lowered by using COB package and eutectic welding process. The chip temperature rises with the decrease of the chip interval. When the thickness of the bonding layer increases, the chip temperature also rises, while the maximum thermal stress decreases. Combining the COB packaging technology with the eutectic welding process can effectively improve the thermal characteristics of high power LEDs. Determining the proper chip interval and thickness of the bonding layer can further improve the thermal characteristics.