Lightweight diamond/Cu interface tuning for outstanding heat conduction

With rapid developments in the field of very large-scale integrated circuits, heat dissipation has emerged as a significant factor that restricts the high-density integration of chips. Due to their high thermal conductivity and low thermal expansion coefficient, diamond/Cu composites have attracted considerable attention as a promising thermal management material. In this study, a surface tungsten carbide gradient layer coating of diamond particles has been realized using comprehensive magnetron sputtering technology and a heat treatment process. Diamond/Cu composites were prepared using high-temperature and high-pressure technology. The results show that, by adjusting the heat treatment process, tungsten carbide and di-tungsten carbide are generated by an in situ reaction at the tungsten-diamond interface, and W-WC-W2C gradient layer-coated diamond particles were obtained. The diamond/Cu composites were sintered by high-temperature and high-pressure technology, and the density of surface-modified diamond/Cu composites was less than 4 g cm(-3). The W-WC-W2C@diamond/Cu composites have a thermal diffusivity as high as 331 mm(2) s(-1), and their thermal expansion coefficient is as low as 1.76 x 10(-6) K-1. The interface coherent structure of the gradient layer-coated diamond/copper composite can effectively improve the interface heat transport efficiency.