Fabrication Of Diamond-like Carbon Films By Ion Enhanced Middle Frequency Unbalanced Magnetron Sputtering

The research background, structure, performance, characterization, application and growth mechanism of diamond-like carbon(DLC) films were first summarized. Then, DLC films were fabricated using Hall plasma source enhanced middle frequency unbalanced magnetron sputtering technique. Effects of substrate bias voltage, substrate temperature, Hall discharge current, ratio of argon and nitrogen and introduction of different transition layers and different substrates on DLC's performance had been investigated. The micro-structure of the films was evaluated by X-ray diffraction; The surface morphology of the films was determined using Scan Electron Microscope and Atomic Force Microscope; the roughness and thickness of the film was measured by Surface Profilometer; the colour of the films was investigated using spectrophotometer; the hardness and Young's modulus were determined by Continuous stiffness method; the bonding force between substrate and films was measured by Revetest Scratch Tester; the friction coefficient between film and coupling materials was detected using Triometer tester. The experimental results are described in details as follows:(1)With the substrate bias voltage increasing, surface roughness of DLC films increases, the proportion of sp bond firstly increases and then decreases, the hardness and Young's modulus keep the same trend with the proportion of sp~3 bond. When substrate bias voltage is -80V, the proportion of sp~3 bond reaches its maximum, meanwhile the maximums of hardness and Young's modulus is 15.23Gpa and 147.245Gpa respectively.(2)As substrate temperature rising, surface roughness of DLC films remain invariable. When substrate temperature is 80℃, sp~3 bond proportion of films is the most. As substrate temperature continuing rising, sp~3 bond proportion gradually decrease. When temperature increases from 80℃ to 120℃, a few well-orderd graphite regions were produced which result in increasing of hardness and Young' modulus. When temperature is 120℃, hardness and Young's modulus are the biggest, 12.549Gpa and 156.211Gpa respectively. As temperature is over 120℃, hardness and Young's modulus sharply decrease.(3)With Hall discharge current increasing, surface roughness of DLC films deposited on stainless steel 316L firstly decreases and then keeps invariable. Surface roughness of DLC films deposited on single crystal Si remains invariable. As Hall discharge current increasing, proportion of sp~3 bond in the films decreases, hardness and Young's also gradually decrease,...