The Aerosol Deposition Method can be used for a wide range of applications.
Electric isolation, heat dissipation and electromagnetic shielding is needed everywhere in the electronic industry. Particularly e-mobility creates new demand. Aerosol deposition produces the required coatings from the raw material or tailored raw material mixtures at room temperature with superior adhesion.
For electrical insulation of power electronics components, ceramic circuit boards are coated with AD-Al2O3. The figures show such a coating on an AMB (Active Metal Brazed) Si3N4 substrate.
Corrosion, scratches – many ways exist to harm a surface, in particular those surfaces that are exposed to high temperatures. Ceramic coatings help to prevent damage.
Abrasion
The graph shows the wear of a stainless steel workpiece under dynamic loading with a ceramic counterpart (pin-on-disc test).Compared to the uncoated base material, the wear on the workpiece with a 5 µm thick AD-Al2O3 coating is significantly lower.
Corrosion
Specialty Ni-alloys for high-temperature applications are susceptible to corrosion. The microscope cross-section shows the improvement in corrosion resistance that can be reached by coating the alloy with aerosol deposition.
Download our case study on service life extension for high-temperature nickel alloys
More and more sensors use thin layers. It can be as passive layer to protect the sensing parts from external influences, e.g., from harmful dopants from adjacent material. Or the active part is composed of a thin layer of the relevant material, as for example in NTCs, gas sensors or piezoelectrics. Using aerosol deposition as coating technique enables superior performance of the devices.
Download Case Study on protective coatings for high-temperature sensors
In semiconductor production, during the plasma etch step of the chip manufacturing process, very aggressive gases reduce the lifetime of the equipment. A by-product of this corrosion is debris from the chamber walls causing off-spec parts on the wafer thus increasing the scrap rate. Depositing etch resistant coatings, for example made of yttria, on exposed parts of the plasma etch chamber significantly reduces this problem. These etch resistant coatings perform best if deposited by aerosol deposition.
The graph shows the comparison of the plasma etch resistance of a conventionally thermally sprayed Y2O3 and an AD-Y2O3 coating. With the latter, the corrosion rate and thus also the removal of particles in a plasma etching chamber is significantly lower.
There are numerous fields of application for antiseptic coatings in medical technology. They often consist of an active component - for example silver - and a carrier material such as ceramics. Aerosol deposition makes it possible to apply both materials at the same time. However, the real strength lies in being able to apply materials and material mixtures where sputtering or evaporation does not work. For example, coating heat-sensitive substrates.
Read more about antiseptic coatings with the aerosol deposition method
Coatings made of hydroxyapatite (HA) are applied to dental or orthopedic implants, for example, dental implants or titanium bone screws. HA is similar to natural bone in its composition and has an osteophilic surface. It is characterized by being biocompatible, bioactive and osteoconductive. This means that such a coating helps the bone to bond with the implant.
Currently, hydroxyapatite coatings are often applied via plasma spray processes. HA coatings applied by aerosol deposition provide dense, crack-free HA films with very good adhesion to the implant.
Silicon Nitride (Si3N4) is a biocompatible ceramic that exhibits anti-viral[1] and anti-bacterial characteristics. Conventional coating technologies like thermal spraying cannot be used for the fabrication of silicon nitride films because of its decomposition at high temperatures. Silicon nitride coatings applied by PVD and CVD are limited to a thickness of several nanometers. By using aerosol deposition several micrometer thick Si3N4 films can be fabricated with outstanding material properties.
Aerosol Deposition Silicon Nitride Coatings Datasheet
[1] Pezzotti, G., Boschetto, F., Ohgitani, E. et al. Silicon nitride: a potent solid-state bioceramic inactivator of ssRNA viruses. Nature Sci Rep 11, 2977 (2021)
