LED导热胶片性能研究与评估

The Research and Evaluation of LED Thermal Interface Materials

大功率LED器件的基座与散热基板之间的接触热阻会阻碍其芯片PN结与散热基板之间的热传导,从而影响到器件的光、色、电性能及寿命。导热胶片用于填充材料界面之间接合或接触时产生的微空隙及表面凹凸不平的孔洞,是减小接触热阻、降低芯片PN结温度的有效手段。文章主要通过测定热阻值来开展对导热胶片在实际应用中导热性能的研究。通过阻容模型、加热曲线及传热结构,深入解析导热胶片在整个LED热管理系统中的工作情况,以及其对器件各部分散热性能的影响,取得有意义的实验结果并且提出一种测试导热胶片性能的新方法。

Contact resistance exists in the contact face between LED （light emitting diode） substrate and heat sink, which will hinder thermal conducting from PN junction to heat sink and affect its light, color, ele ctrical performance and lifetime. Thermal interface materials can be used to fill the holes and gaps between the contact face. This method can reduce contact thermal resistance and the temperature of PN junction. The thermal properties of thermal interface materials were studied by measuring its thermal resistance. In addition, its role in the LED cooling system can be analyzed by RC model, heating curve, structure function. This paper proposed a new testing method of thermal interface materials.