In the past, plastic pvd coating machines and decorative pvd coating machines were relatively common. Few people knew about optical pvd coating machines. They always felt that the high-tech content of optical coating machines was very high, and it was far away from us. Now, optical vacuum coating machines It has been used in many industries and recognized by many manufacturers. The following is a small series of vacuum coating to explain the knowledge of optical pvd coating machine maintenance.

Optical pvd coating machine is mainly composed of pvd coating machine room, vacuum pumping unit and electric cabinet (control electric cabinet, electron gun electric cabinet), which is widely used in microelectronics, optical film forming, civil decoration, surface engineering and other fields. Its working principle is to use electron beams to heat metal or non-metal materials to an appropriate temperature in a high vacuum state, and the materials evaporate into vapor molecules after being heated. Its mean free path is larger than the distance from the evaporation source to the substrate to be evaporated, and the evaporated vapor molecules are directed to all directions, and when they touch the substrate, they are deposited on the surface of the substrate to form a film layer. The maintenance and maintenance of the optical coating machine mainly includes the installation and maintenance of the electron gun, the repair and maintenance of the optical path, and the cleaning and maintenance of the equipment.
1. Electron gun installation and maintenance
        Electron gun evaporation source control system is composed of electron gun filament power supply, high voltage power supply, scanning power supply, crucible driving power supply, evaporation source, etc. to form an electron gun control cabinet. The electronic gun control cabinet contains high voltage, and each interlocking device of the cabinet door must be in normal operation before working. Connect to the machine ground. The evaporation source of the electron gun is installed on the bottom plate of the vacuum chamber, and must have a good grounding effect with the bottom plate. The installation of the evaporation source must be fixed with stainless steel screws, and there must be no magnetically conductive objects within 200mm of the surrounding area, otherwise it will affect the beam spot of the electron gun. Poor electronic performance. The electron gun baffle should be installed as far as possible at 30mm above the center of the crucible of the evaporation source, so as not to affect the emission of the electron beam. The electron gun evaporation source is a precision machined body, and it must have good cooling water during operation. For example, too high temperature will affect the forming of the electron beam and the performance of each sealing ring. 
      (1) Electron gun head
       The installation of the gun head of the electron gun directly affects the normal operation of the work, and 90% of the failures are related to the gun head of the electron gun. After the electron gun tip has been used for a period of time, the formation and power of the electron beam will be affected by the contamination of the components, and it needs to be disassembled and cleaned.
      (2) Maintenance of the crucible
       Before dismantling the crucible, please turn off the water circuit and use compressed air to blow out the moisture in the electron gun cooling tube as much as possible.
Evaporation source loading and unloading sequence:
      1. Remove the two cooling water connecting pipes.
       2. Unscrew the two screws of the electron gun head to connect the high voltage line.
       3. Remove the crucible drive connecting seat and coupling.
       4. Unscrew the four fixing screws of the evaporation source.
       5. Move the evaporation source to a stable and flat workbench.
       6. Remove the four screws of the crucible cover, remove the cover and polish it clean.
       7. Check whether the two sealing rings above the cover plate need to be replaced.
       8. Turn the evaporation source upside down, and use a wooden board to cover the crucible part.
       9. Unscrew the fixed crucible and turn the four screws
      10. Lift the evaporation source and remove the crucible
      11. Turn the crucible upside down, unscrew the eight screws of the bottom cover of the crucible, clean the dirt inside, and check whether the near-sealing ring is needed.
      12. Unscrew one screw of the aqueduct
      13. Unscrew the four screws connecting the crucible rotating mechanism and the crucible cover
      14. Pull out the crucible rotating shaft and check whether the oil seal of the rotating shaft needs to be replaced. 15. Clean and install the crucible. The installation is performed in the reverse order above.
   (3) Maintenance of the magnetic guide plate and the scanning ring
       The magnetic guide plate and permanent magnet do not need frequent disassembly and maintenance. If you need to disassemble, please pay attention to the pole direction of the permanent magnet and the direction of the magnetic guide plate. Due to the dense installation space of the coil, please do not use a hard-pointed object to pry it, otherwise it may cause damage.
2. Inspection and maintenance of optical path
       The prerequisite for optical path adjustment is to ensure the complete and correct connection of DC stable power supply, modulated light source head, optical fiber, grating monochromator, photoelectric conversion amplifier, optical film thickness meter and various special cables. In particular, the grounding point of the photoelectric conversion amplifier and the optical film thickness measuring instrument must be separately assigned to the host contact and firmly grounded.
       In the daily process of the optical pvd coating machine, maintenance is very necessary. When the machine runs for a long time, there will be some wear and tear. Timely maintenance will reduce a lot of unnecessary obstacles for the later stage, and also make the machine use longer. long.