Critical coating machines are used to coat surfaces of critical parts such as wafers, storage discs or other electronic components, biotechnology devices or pharmaceutical equipment parts. The smallest amount of remaining contaminants on the surface can result in a defect causing the scrapping of the products. Equipment designed to deposit coatings for electronic components applications such as printed circuit boards (PCB, PWB), flexible circuits, silicon wafers, semiconductors or IC chips, IC packages and reel-to-reel connectors or lead frames. For example, critical coating machines may apply a dielectric conformal coating to insulate and protect the PCB or flexible circuit. Other PCB coating equipment can selectively apply conductive metal pastes or solders to form circuitry or aid in forming soldered connections. Thick film and thin film circuits are also formed using coating techniques. For example, critical coating machines
may apply a photoresist resins as part of the photolithography process. Spin coaters are typically used to apply photoresist. Dopants (SOG type) and dielectric layers are often applied to wafers using spin coating techniques. Other PCB coating equipment can selectively apply conductive metal pastes or solders to form circuitry or aid in forming soldered connections. Wafer level metallization and thin film circuits or interconnect are also formed using PVD, CVD and ECD coating techniques.