The vacuum vapor deposition process generally includes steps such as substrate surface cleaning, preparation before coating, vapor deposition, picking up pieces, post-plating treatment, testing, and finished products.
(1) Substrate surface cleaning. Vacuum chamber walls, substrate frame and other surface oil, rust, residual plating material is easy to evaporate in a vacuum, directly affecting the purity of the film layer and the bonding force, must be cleaned before plating.
(2) Preparation before coating. Coating empty vacuum to the appropriate vacuum degree, the substrate and coating materials for pretreatment. Heating the substrate, the purpose is to remove moisture and enhance the membrane base bonding force. Heating the substrate under high vacuum can desorb the adsorbed gas on the surface of the substrate, and then exhaust the gas out of the vacuum chamber by the vacuum pump, which is conducive to improving the vacuum degree of the coating chamber, the purity of the film layer and the bonding force of the film base. After reaching a certain vacuum degree, the first evaporation source with a lower power of electricity, the film preheating or pre-melting. In order to prevent evaporation to the substrate, cover the evaporation source and source material with a baffle, and then enter a higher power of electricity, the coating material is rapidly heated to the evaporation temperature, evaporation and then remove the baffle.
(3) Evaporation. In addition to the evaporation stage to choose the appropriate substrate temperature, plating material evaporation temperature outside the deposition of air pressure is also a very important parameter. Deposition of gas pressure that is the coating room vacuum, determines the average free range of gas molecules moving in the evaporation space and a certain evaporation distance under the vapor and residual gas atoms and the number of collisions between the vapor atoms.
(4) Unloading. After the thickness of the film layer to meet the requirements, cover the evaporation source with a baffle and stop heating, but do not immediately guide the air, the need to continue to cool under vacuum conditions for a period of time to cool down, to prevent plating, residual plating material and resistance, evaporation source and so on oxidized, and then stop pumping, and then inflate, open the vacuum chamber to take out the substrate.
–This article is released by vacuum coating machine manufacturer Guangdong Zhenhua
Post time: Aug-23-2024