Vacuum deposition, also known as vacuum evaporation, is a process used to deposit material onto a surface with minimal or no gas molecules between the material and surface. Under vacuum, the coating process deposits material on the atomic or molecular level. Layers of material can range from an atom to millimeters thick.
Vacuum deposition can be based on the vapor source; physical vapor deposition uses a liquid or solid source while chemical vapor deposition uses a chemical vapor.
Chemical vapor deposition (CVD) (a vacuum deposition method) produces high quality, high-performance, solid materials. Semiconductor industry often uses this process to produce thin films. In the CVD process, the wafer (substrate) exposed to one or more volatile precursors reacts and/or decomposes on the substrate surface to produce the desired deposit. This process produces volatile by-products periodically. Provided that, gas flow through the reaction chamber removes all the by-products. The CVD process deposits many substances including: silicon (dioxide, carbide, nitride, oxynitride), carbon (fiber, nanofibers, nanotubes, diamond and graphene), fluorocarbons, filaments, tungsten, titanium nitride and various high-k dielectrics.
Vacuum deposition also forms optical interference coatings, mirror coatings, decorative coatings, permeation barrier films on flexible packaging materials. Furthermore, it forms electrically conducting films, wear resistant coatings, and corrosion protective coatings.
Overall Wintek has designed and consulted on systems for vapor deposition providing more than 9000 ACFM at 0.2 mmHgA. Due to the low absolute operating pressure, Wintek generally recommends dry pumps. While costly, these pumps are able to pull high vapor loads at low absolute pressure.