Cho Hyun Min, Kim Min-Sun
J Nanosci Nanotechnol. 2014 Aug;14(8):5824-7. doi: 10.1166/jnn.2014.8315.
In this study, we developed AlN thick film on metal substrate for hybrid type LED package such as chip on board (COB) using metal printed circuit board (PCB). Conventional metal PCB uses ceramic-polymer composite as electrical insulating layer. Thermal conductivities of such type dielectric film are typically in the range of 1~4 W/m · K depending on the ceramic filler. Also, Al or Cu alloy are mainly used for metal base for high thermal conduction to dissipate heat from thermal source mounted on metal PCB. Here we used Cu-W alloy with low thermal expansion coefficient as metal substrate to reduce thermal stress between insulating layer and base metal. AlN with polyimide (PI) powder were used as starting materials for deposition. We could obtain very high thermal conductivity of 28.3 W/m · K from deposited AlN-PI thin film by AlN-3 wt% PI powder. We made hybrid type high power LED package using AlN-PI thin film. We tested thermal performance of this film by thermal transient measurement and compared with conventional metal PCB substrate.
在本研究中，我们在金属基板上制备了用于混合式发光二极管封装（如采用金属印刷电路板（PCB）的板上芯片（COB））的氮化铝厚膜。传统的金属印刷电路板使用陶瓷 - 聚合物复合材料作为电绝缘层。这种类型的介电膜的热导率通常在1~4 W/m·K范围内，这取决于陶瓷填料。此外，铝或铜合金主要用作金属基底，以实现高导热性，从而消散安装在金属印刷电路板上的热源产生的热量。在此，我们使用具有低热膨胀系数的铜钨合金作为金属基板，以降低绝缘层与基底金属之间的热应力。氮化铝与聚酰亚胺（PI）粉末用作沉积的起始材料。通过使用3 wt% PI粉末的氮化铝，我们从沉积的AlN - PI薄膜中获得了高达28.3 W/m·K的热导率。我们使用AlN - PI薄膜制作了混合式高功率发光二极管封装。我们通过热瞬态测量测试了该薄膜的热性能，并与传统金属印刷电路板基板进行了比较。
