Physical vapor deposition (PVD) refers to a thin-film deposition technique employed in materials science and engineering. It involves the process of depositing a layer of material onto a surface through a physical vaporization method. PVD utilizes physical phenomenon, specifically the transformation of a solid substance into a vapor form, without undergoing the liquid phase.
In the PVD process, a high-energy physical vapor source, typically in the form of a solid material, is heated to an elevated temperature. As a result, the atoms or molecules making up the source material gain sufficient thermal energy to break their interatomic or intermolecular bonds, transitioning into a vapor state. This vapor, also known as a plasma, is then directed towards the target surface where it condenses and forms a thin layer by adhering to the substrate.
PVD offers numerous advantages including exceptional control over film thickness, compositional uniformity, and high purity. This method finds application in various industries, such as electronics, automotive, aerospace, and decorative coatings. It is commonly used for surface modification, protective coatings, and the production of optical coatings, as well as for improving wear resistance, hardness, and corrosion resistance of materials.
Physical vapor deposition techniques include evaporation, sputtering, and cathodic arc deposition. Each technique employs different principles for vaporizing the source material and applies specific strategies to control the direction, energy, and intensity of the generated vapor. These variations allow for customization of coating properties, making PVD a versatile and highly adaptable method for thin-film deposition.
