Effect of Bias Voltage on Heat Dissipation Application of Diamond-like Carbon Films
In this paper, aiming at development in heat dissipation layer for commercial electronics products, hydrogen-free diamond-like carbon (DLC) films have been deposited on copper foil at room temperature using unbalanced magnetron radio frequency sputtering technique with a novel nanodiamond target. Moreover, DC bias for Cu foil was optimized to improve the characteristics of the as-prepared DLC film. The effects of the applied substrate bias on surface morphology and microstructure of the DLC films were systematically investigated by scanning probe microscopy, Raman spectroscopy, X-ray photoemission spectroscopy, and atomic forced microscopy. The results shown that the films deposited under DC bias of -45 V possessed uniform surface morphology, high sp3 content and low surface roughness. A large area of DLC/Cu foil was fabricated for thermal diffusion test with heat source power of 3 W and working temperature of 50oC. The data reveals that the thermal diffusivity of the Cu foil heat sink were improve by 22 % by using DLC films. The aforementioned results indeed open up an avenue for the uses of DLC materials in heat dissipation applications in advance electronics products. Keywords - Diamond-Like Carbon, Heat Dissipation, Sputter.