Compliance-tunable thermal interface materials based on vertically oriented carbon fiber arrays for high-performance thermal management

Abstract

With the ever-shrinking characteristic dimension of chips and the increasing of packaging density, heat dissipation has become the most critical technology challenge for electronic devices. The development of high-performance thermal interface materials (TIMs) for enhancing thermal coupling and minimizing thermal resistance between heterogeneous components is the key to achieving efficient thermal management of electronic devices. Herein, we report a high-performance carbon fiber/polydimethylsiloxane (CF/PDMS) TIM based on the construction of vertically oriented carbon fiber arrays and the modulation of PDMS's crosslinking density. The resulting CF/PDMS TIM exhibits highly desirable characteristics of through-plane thermal conductivity up to 43.47 W/m∙K (only 20 vol% loading), outstanding elastic compliance similar to soft biological tissues (stress ∼ 35 kPa at 35% compressive strain), and excellent resilience performance (resilience rate of 85% after compression cycles). In addition, the heat dissipation capability of CF/PDMS TIM is improved further by forming interconnected heat-conducting structures on the CF/PDMS TIM's surface. The optimal CF/PDMS TIM in microprocessor cooling application exhibits superior heat dissipation capability and stability during 1000 power cycles, resulting in a 68 °C reduction in the chip temperature compared with the state-of-the-art commercial TIM. This work opens up a new avenue for fabricating high-performance TIMs that meet the heat dissipation requirements of high-performance computing.