DLC film, also known as diamond-like film, has good mechanical properties, electrical properties, optical properties, extremely high hardness, resistivity, electrical insulation strength and thermal conductivity, high infrared transmittance and optical refractive index, as well as good Due to its chemical stability and biocompatibility, it has a wide range of applications. Therefore, the DLC process prepared by a pvd coating machine has also attracted special attention from the market. The number ratio of sp3 bonds to sp2 bonds in the DLC film is the main factor that determines the hardness of the diamond-like carbon film. The larger the value, the higher the hardness. Therefore, the diamond-like film has an adjustable high hardness, and its upper limit of hardness value is close to the hardness of diamond (100 GPa), reaching 95GPa. Hardness is related to DLC structure.

Therefore, it is related to the preparation method. The DLC film prepared by the magnetic filtration cathode arc method (FVCA) has a hardness similar to that of the diamond film; the hardness of the DLC film prepared by the vacuum cathode arc method (VCAD) is above HV5000; while the hardness of the DLC film prepared by the magnetron sputtering method is above HV5000. The hardness of the DLC film is relatively low, generally below HV2000. In addition, the deposition process and doping also have an impact on the hardness of the DLC film. Appropriate bias, pressure and atmosphere can improve the hardness of the DLC film to varying degrees. Most experiments show that doping The hardness of the DLC film decreases to varying degrees, but some people think that the incorporation of Si can improve the hardness of the DLC film. There is generally a large internal stress in the DLC film. The internal stress is not only related to the structure and composition of the DLC film, It also has a lot to do with the film forming process. For example, in the H-DLC film, the internal stress has a great relationship with the H content.

The pvd coating machine deposits DLC thin film. While maintaining the high hardness of the DLC film, the incorporation of N, Si and certain metal elements can reduce the internal stress. The internal stress has a great influence on the bonding performance of the DLC film and the substrate. Directly on the substrate When depositing a DLC film, the bonding force of the film is generally poor. The thinner the DLC film, the better the bonding force between the film and the substrate. In addition, the adhesion of the film can also be enhanced by adding a transition layer between the DLC film and the substrate. For example, Using Cr as the transition layer significantly improves the bonding between the film and the substrate; different substrates have different transition layers. Because the DLC film has high hardness, it has excellent wear resistance, and its friction coefficient is low, so it is an excellent surface modification material. Because the DLC film has the above excellent properties, it has been widely used. DLC The film is very suitable for tool coating. The preparation process of DLC film has developed rapidly, and a variety of preparation methods have been developed. These methods are generally divided into two categories: physical vapor deposition (PVD for short) and chemical vapor deposition. (chemical vapor deposition referred to as CVD) and plasma enhanced chemical vapor deposition (PECVD).
The PVD coating method of pvd coating machine includes vacuum evaporation, resistance heating evaporation, induction heating evaporation, hot cathode ion plating, arc ion plating, active reactive ion plating, radio frequency ion plating, DC discharge ion plating, etc. Its outstanding feature is that it combines various Gas discharge introduces gas phase deposition, so that the entire deposition process is carried out in plasma, which greatly increases the particle energy. Ion plating has a fast film formation speed, good film base bonding force, good film wrap-around properties, and can be used at lower temperatures. Deposition is carried out under the conditions. The magnetic filter cathode vacuum arc deposition (FCVA) technology uses a magnetic filter coil to filter out large particles and neutral atoms generated by the arc source, so that almost all of the carbon ions that reach the substrate are carbon ions, which can be prepared at a higher deposition rate. A hydrogen-free DLC film was produced. Some people used FCVA technology to make a hydrogen-free carbon film with an sp3 bond content of up to 90% and a hardness of up to 95 GPa. Its properties are similar to polycrystalline diamond materials. Sputtering plating uses glow discharge and cathode sputtering. The coating is based on the principle. The magnetron sputtering method uses argon ions Ar to sputter the graphite target through DC intermediate frequency or radio frequency. The energy distribution of the sputtered carbon atoms varies depending on the energy and type of the sputtered ions. The advantages of this method The deposition temperature is low, the equipment is simple, the deposition area is large, and high-resistance films and insulating films can be deposited.