The products to be metallized can be made of plastic, glass, ceramic or metal. The aim of metallization is to increase product value by:
- improving reflectivity
- achieving decorative surface effects
Metals such as Al, Au, Ag, NiCr etc. are vapour-deposited in a vacuum. These become deposited on the substrates in the form of a thin layer.
The technology of metallizing product surfaces consists of several part-steps in which the substrate material, the layer material and the requirements profile all play a key role and therefore require careful selection and matching to requirements.
The parts to be coated are fixed to a rotating cage in the vacuum chamber and during vapour-deposition, rotate around the evaporator unit either once or several times. Part-areas which are not yet to be metallized are masked off.
In addition to the resistance-heated sources, magnetron sputtering sources are available to deposit metals.
Depending on the application, typical layer thickness is in the range from 50 nanometres (0.00005 mm) to a few microns.
It is possible to protect the deposited layer from mechanical damage or oxidation with an HMDS polymer layer or, if necessary, with a SiO2 layer.