Physical vapor deposition (PVD for short) technology refers to the use of physical methods to vaporize materials into atoms, molecules or ionize them into ions under vacuum conditions, and deposit a layer with a certain Film technology with some special properties.
The main methods of physical vapor deposition technology are: vacuum evaporation, sputtering coating (vaouulnl-ttering), high son coating (ioaplating).
Vacuum coating is a method of depositing metal alloys or compounds on the surface of a substrate under vacuum conditions. It uses resistance heating, high-frequency induction heating or high-energy beams (electron beams, laser beams, ion beams) Etc.) surface strikes to transform the deposition material (or coating material) into a gas phase to achieve the purpose of deposition. Vacuum evaporation is an earlier technology in the PVD method_sputtering coating is under certain vacuum conditions filled with argon , using the photolysis discharge technology, the argon gas is charged to generate argon electrons, and the argon ions are accelerated to bombard the cathode under the action of the electric field force, so that the cathode material is sputtered and deposited on the surface of the workpiece to form a coating method. It appeared earlier The sputtering coating method is the radio frequency sputtering method proposed by the Americans.
Ion plating is a method of using various gas discharge technologies under vacuum conditions to partially ionize the atomic atoms into high electrons, and at the same time generate a large number of high-energy neutral particles to deposit on the surface of the workpiece to form a coating. High ion plating was first developed by Proposed by SANDIA Corporation of the United States, in the sputtering coating and hypertronic coating methods, due to the improvement of evaporation, sputtering and electro-high technology, many new coating methods have been produced, but they still belong to sputtering sensitive film and ion sputtering. The category of coating. Some methods have some characteristics of this Western method, so it is difficult to clarify its specific attribution.
Suitable for substrate materials and film materials of physical vapor deposition. Metals, glass, ceramics and plastics can be used as substrate materials. Film materials can be pure metals, alloys or compounds, and can be obtained from single crystal, multi-product, Thin films with microcrystalline or amorphous structure (instrument: thin Film Thickness Gauge).
The process of all methods of physical vapor deposition technology can be divided into three steps. The first step is the gasification of the film-forming material, that is, the expression, sublimation, sputtering, and decomposition of the film-forming material, which is the source of the film-forming material. ; The second step is the transfer process of film-forming atoms, molecules or hyperons from the source to the substrate, during which collisions may occur between particles, resulting in heightening, recombination, reaction, energy change and change of motion direction, etc. A series of complex processes; the third step is the adsorption of film-forming atoms on the surface of the substrate: accumulation, nucleation and growth into film.
Physical vapor deposition has the characteristics of simple process, material saving, no pollution, uniform film thickness, dense film layer, strong adhesion to the substrate material, etc., and the temperature is low during the process, the workpiece becomes smaller, and it will not Annealing softens, and generally does not need to be reprocessed. Recently, physical vapor deposition technology has been widely used in the fields of machinery, aerospace, electronics, optics, light industry and construction industry, for the preparation of wear-resistant, heat-resistant, conductive, insulating, Optical, magnetic, piezoelectric, lubricating, conductive, decorative and other thin films. With the development of modern industrial technology and new requirements for material performance, physical vapor deposition technology is also developing continuously, and its application objects will also be continuously expanded, and the applied equipment will be large-scale, effective and general-purpose. development in the direction of automation and automation.
