Vacuum chambers, components and related systems consist of various materials according to requiring material performance. Austenitic stainless steels have been used for vacuum chambers due to high mechanical strength, anti-corrosion and low outgassing. Aluminum alloy have been used for special vacuum systems such as particle accelerator due to non-magnetism and low radioactivation. Copper has been used for flange gasket due to good ductility. Ceramics have been used for components of electrical insulator, high temperature system and so on due to good stability under harsh environments. Organic materials are less used due to their high outgassing rate compared with inorganic materials. It is important to select and put the right material in the right place in a vacuum system.
The gas pressure of a vacuum system is determined by the outgassing from its surfaces. Outgassing can be categorized into desorption, diffusion and permiation. In this text, the mechanisms of these modes, as well as the countermeasures for them, are discussed. Some methods to evaluate the outgassing rate are also introduced.
Thin films have recently emerged as one of the most important building blocks of nanotechnology and are often prepared under vacuum conditions. For efficient production of high-quality thin films, it is important to understand the impact of the vacuum on each stage of the thin film deposition processes, including decomposition of the starting material, transport of its vapor, and deposition. This article discusses the general key aspects of the thin film deposition process from the viewpoint of vacuum science and technology.
Discharge plasma, especially that generated at low gas pressures, is an important application of vacuum technology. This article describes the unique features of low gas pressure plasma, generation of plasma discharge and various plasma parameters. Plasma-wall interaction, which is very important for many plasma-related technologies, is also discussed considering the collisionless sheath model.