vapendeposition

Vapendeposition, usually written as vapor deposition (or vapour deposition), refers to a family of methods for producing thin solid films from a vapor phase and depositing them on a substrate. It includes techniques that deposit material by physical transfer as well as those based on chemical reactions in the gas phase. The term is sometimes used loosely; most writers distinguish physical vapor deposition (PVD) and chemical vapor deposition (CVD).

Physical vapor deposition involves physically removing material from a source and transporting it to the surface. In evaporation, the source is heated under vacuum to form a vapor that condenses on the substrate. In sputtering, energetic ions strike a target, ejecting atoms that are then deposited. PVD typically yields dense, well-adhered films and is common for metals and ceramics, with good thickness control and step coverage on complex geometries.

Chemical vapor deposition uses gaseous precursors that react at the substrate surface to form solid films. Variants include thermal CVD, plasma-enhanced CVD (PECVD), and low-pressure CVD (LPCVD). CVD can produce high-purity, conformal coatings and is widely used in semiconductors, optics, and protective layers. Atomic layer deposition (ALD) is a related technique that builds films one atomic layer at a time, offering exceptional conformity.

Key considerations include substrate temperature, chamber pressure, gas composition, and deposition rate. Film properties such as crystallinity, stress, and purity depend on process conditions. Advantages include the ability to coat complex geometries with uniform coverage; challenges include equipment costs and impurity management. Vapendeposition underpins technologies from microelectronics to protective and optical coatings.