Fabrication and Analysis of High Quality Diamond Like Carbon Film

Diamond like carbon (DLC) films were deposited on Si(100) substrate by coupling DC/RF magnetron sputtering. The chemical compositions of DLC films were characterized by Raman spectroscopy and X-ray photoelectron spectroscopy. The mass density of DLC films was investigated by X-ray reflectivity. The internal stress of DLC films was measured by substrate curvature method. The surface roughness and surface morphology were characterized by atomic force microscopy and scanning electron microscopy, respectively. It is found that sp³ content in the films first increases then decreases with the RF power increasing, and reaches the maximum value of 45.6% at 40 W RF power. With the RF power increasing, the surface roughness first decreases then increases and gains the minimum surface roughness of 1.6 nm at 40 W RF power. The internal stress of DLC films deposited by coupling DC/RF magnetron sputtering is lower than 1.0 GPa, and mass density varies from 2.26 g/cm³ to 2.44 g/cm³. So, this method would be really an effective method to prepare high quality DLC films with low internal stress and high mass density.