Deformable surface design of vertical graphene thermal interface materials for efficient heat dissipation
Chao Tian, Huaqiang Fu, Zhe Wang, Zixin Zhang, Wei Qian, Huazhang Zhang, Shiqi Xu, Shiya Cao, Daping He
Abstract
Vertical graphene, serving as a thermal interface material (TIM), is very promising for efficient thermal dissipating. Yet, the heat-dissipating efficiency is mediocre since satisfactory through-plane thermal conductivity ( κ ⊥ ) and contact thermal resistance ( R contact ) cannot be obtained simultaneously. In this work, we achieve TIMs with ultrahigh κ ⊥ (738.6 W m −1 K −1 ) and low R contact (29.2 K mm 2 W −1 ) based on volume shrinkage of silver paste within vertical graphene monoliths (VGMs). The outstanding κ ⊥ derives from vertically arranged graphene films (GFs) with excellent in-plane thermal conductivity. Besides, the silver pastes between GFs shrink after heating, triggering exposure of soft GF ends and forming a deformable surface to realize a notable decrease in R contact . Our VGM TIMs display an enhancement in thermal dissipating efficiency of ∼2.44 times compared to that of the state-of-the-art TIMs. Our findings offer practical design guidelines for advanced TIMs and thermal management applications.