An Optimal Cure Process to Minimize Residual Void and Optical Birefringence for a LED Silicone Encapsulant

Materials

Min-Jae Song¹  Kwon-Hee Kim²  Gil-Sang Yoon¹  Hyung-Pil Park¹ 

[1] Molds & Dies Technology R&DB Group, Korea Institute of Industrial Technology, 7-47, Songdo-dong, Yeonsu-gu, Inchoen 406-840, Korea; E-Mails:;Department of Mechanical Engineering, Korea University, Anam-dong, Seongbuk-gu, Seoul 136-713, Korea; E-Mail:

关键词: LED;    silicone resin;    encapsulant;    multi-step cure process;    voids;    birefringence;    residual stress;    cure kinetics;   

DOI  :  10.3390/ma7064088

来源: mdpi

【 摘 要 】

Silicone resin has recently attracted great attention as a high-power Light Emitting Diode (LED) encapsulant material due to its good thermal stability and optical properties. In general, the abrupt curing reaction of the silicone resin for the LED encapsulant during the curing process induces reduction in the mechanical and optical properties of the LED product due to the generation of residual void and moisture, birefringence, and residual stress in the final formation. In order to prevent such an abrupt curing reaction, the reduction of residual void and birefringence of the silicone resin was observed through experimentation by introducing the multi-step cure processes, while the residual stress was calculated by conducting finite element analysis that coupled the heat of cure reaction and cure shrinkage. The results of experiment and analysis showed that it was during the three-step curing process that the residual void, birefringence, and residual stress reduced the most in similar tendency. Through such experimentation and finite element analysis, the study was able to confirm that the optimization of the LED encapsulant packaging process was possible.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.