(321d) Radio Frequency-Assisted Curing of on-Chip Printed CNT/Silicone Heatsinks Produced By Diw 3D Printing

With the rapid development of high-power integrated electronic devices in recent years, many polymer-based thermal management devices have been developed to address the overheating and improve the performance, reliability, and lifetime of electronic devices. Here, we demonstrate carbon nanotube (CNT)/silicone heatsinks by Direct Ink Writing (DIW) 3D printing and applied Radio Frequency (RF) heating for in situ curing. CNTs were used as a thermal conductive nanofiller and a rheological modifier to improve thermal conductivity and printability of the CNT/silicone composite inks, respectively. Additionally, CNTs are also a RF susceptor, so the integration of CNTs into the silicone matrix allowed rapid out-of-oven curing by applying RF heating. Specifically, at CNT loading of 14 wt.%, the CNT/silicone heatsinks could be printed and RF cured with shape retention; the heatsinks’ performance was comparable to that of commercial heatsinks. More importantly, the CNT/silicone heatsinks could be printed and cured directly on a chip attached to a circuit board, potentially eliminating the use of thermal interface materials and the step of heatsink installation. The results suggest that the DIW combined with RF assisted curing process can be an effective approach to fabricate high-performance polymer-based heatsinks with reduced production time and energy requirements.