What is Evaporative Deposition?
Evaporative deposition is a manufacturing process that involves the deposition of a thin film of material onto a substrate by vaporizing a source material and allowing the vapor to condense onto the substrate. This process is commonly used to create thin film coatings or layers of materials that have specific properties or functions, such as insulation, conductivity, or wear resistance.
One of the main advantages of evaporative deposition is that it allows for the precise control of the thickness and composition of the deposited film. This is because the rate of deposition is determined by the vapor pressure of the source material and the temperature of the substrate, which can be carefully controlled during the process.
There are several different techniques that can be used for evaporative deposition, including thermal evaporation, electron beam evaporation, and sputter deposition.
- Thermal evaporation is the most common method and involves heating the source material to a high temperature until it vaporizes and then allowing the vapor to condense onto the substrate.
- Electron beam evaporation involves using a beam of high-energy electrons to vaporize the source material,
- …and sputter deposition uses a plasma or ion beam to sputter, or knock off, atoms from the source material, which then condense onto the substrate.
Industries
Evaporative deposition is used in a variety of industries, including electronics, optics, and aerospace, to create thin film coatings for a wide range of applications.
In the electronics industry, evaporative deposition is used to create thin film coatings for conducting, insulating, and protective layers on semiconductor devices. In the optics industry, it is used to create thin film coatings for lenses and other optical components to improve their performance. In the aerospace industry, evaporative deposition is used to create thin film coatings for jet engine parts to improve their wear resistance and durability.
There are several factors that can affect the quality and performance of thin films produced through evaporative deposition, including the purity of the source material, the temperature and pressure conditions during the process, and the substrate surface preparation. Proper control of these factors is essential to produce high-quality thin films with the desired properties and performance.
Dimension Considerations
Some common limitations of roll-to-roll evaporative deposition include:
- Width: The width of the substrate material is typically limited by the size of the rollers used to feed it through the processing stations. These rollers may have a maximum width that they can accommodate, which in turn limits the width of the substrate material that can be processed.
- Length: The length of the substrate material is typically limited by the size of the rollers and the length of the processing stations. If the substrate material is too long, it may not fit onto the rollers or may require additional processing stations, which can increase the cost and complexity of the process.
- Thickness: The thickness of the substrate material and the thin films deposited onto it are typically limited by the evaporation techniques used in the process. Some materials may not be able to be evaporated or may not produce a stable film when evaporated at certain thicknesses.
VDI offers Evaporation, also known as Vapor or Thermal, in web widths of 80 inches and thicknesses of 10 mil to 36GA (9 micron). Additional substrates include PET, Nylon, other web polymers, fabrics, and foils. VDI’s capabilities enable it to provide tight tolerances and uniformity of metal deposition, cross web, down-web, and roll-to-roll.
Additionally, VDI’s Louisville, KY plant also has an in-line plasma treater for this kind of deposition contracting service. An in-line plasma treater is a type of equipment that is used to apply plasma treatment to a substrate as it is being continuously processed. Plasma treatment is a process that involves the use of a plasma, which is a gas that has been ionized to produce a mixture of positively and negatively charged particles. Plasma treatment can be used to modify the surface properties of a material, such as its wettability, adhesion, and surface energy.
Our in-line plasma treatment ensures improved metal adhesion in films using controlled VLT deposition at a maximum speed of 800 meters per minute.
Substrates
Meanwhile, metals are commonly used as substrates in evaporative deposition due to their high temperature stability, good conductivity, and ease of processing. In addition, metals can be easily cleaned and prepared for use as a substrate, which is important for producing high-quality thin films.
VDI offer a number of metal options, among other materials. One example of our capabilities here is aluminum where vapor deposition range from 100 to 4,000 Angstroms, from 0.15 to 4.0 optical density, 70% visible light transmission to opaque, and resistance to meet varied needs. VDI’s metallizer is wire feed and boat capable.
Evaporative deposition is a versatile and precise manufacturing process that is widely used to create thin film coatings and layers of materials with specific properties and functions. VDI has been a leader in evaporative deposition contractors since its founding in 1971. VDI is an active member and contributor of the Association of Industrial Metallizers, Coaters and Laminators (AIMCAL), is also an active member of the Society of Vacuum Coaters (SVC).