Synergistic Enhancement of Thermal Conductivity Through Nano Diamond Coordinated Boron Nitride

The characteristics of films possessing both outstanding flexibility and thermal conductivity are key for flexible integrated microelectronic devices. The main issue is how to integrate diamond into thin films to improve thermal conductivity. The boron nitride-nano diamond/polyurethane (BN-ND/PU) composites are prepared through a novel surface modification-assisted electrostatic bonding technique. A notable temperature reduction between the heat source and the film’s surface by integrating a 33% BN-ND into the PU matrix. A large resistance of the BN-ND/PU complexes is 57.1 M
$\cdot\Omega$
at 75
$^{\circ}$
C, preserving its excellent insulation properties. The CPU core temperature is observed to be 2
$^{\circ}$
C–3
$^{\circ}$
C cooler than that obtained using commercial silicone grease in personal computer. The thermal conductivity of the silicone grease is measured to be 2.537 W/(m
$\cdot$
K) by the steady-state heat flow method. The mechanism can be ascribed to the role of interface diffusion within the BN-ND composites.