PLASMA Coating
Plasma Beschichtungen
A wide range of surface properties can be realized with plasma coatings, which are used in the following fields of application, among others:
Applications
- Wear protection for precision parts
- Coating of medical implants and surgical instruments with biocompatible carbon layers
- Increased corrosion protection
- Reduction of frictional forces; e.g. in plain bearings
- Decorative layers
- Hydrophilic or hydrophobic surfaces
We use various processes to produce coatings with the aid of plasmas:
Sputtering
"Sputtering is a PVD (physical vapour deposition) process in which the material to be deposited is atomized by bombarding a target (sputtering target) with plasma ions. This particle vapor then condenses as a thin layer on the substrate. In order to obtain the necessary conditions for the formation of a plasma, a process gas (generally argon) is introduced into the process chamber at a pressure range of 0.1-1 Pa and a specially shaped magnetic field is generated on the surface of the sputtering target.
By adding further reactive gases, such as N2 or O2, both nitride and oxide layers are produced together with the sputtered metal atoms.
The electric field required to generate the plasma can be applied via a direct voltage (DC plasma) or a time-varying voltage.
PECVD (Plasmaunterstützte chemische Gasphasenabscheidung)
Plasma Enhanced Chemical Vapor Deposition (PECVD) for the production of thin, functional layers. In the PECVD process, the gaseous or liquid precursors (e.g. HMDSO) are activated by radio frequency (RF) or microwave excitation. The plasma facilitates the deposition of coatings at low temperatures (room temperature). As a result, materials with customized properties can be deposited on temperature-sensitive substrates such as polymers.
HIPIMS (High-Power Impulse Magnetron Sputtering)
In high-power impulse magnetron sputtering, the plasma is switched on in very short pulses of typically 50 µs. This allows high plasma densities to be generated at comparatively low average power. This creates very effective additional possibilities for influencing layer growth and producing layers with improved or new properties. By adjusting coating parameters, the HIPIMS process can be used to produce individual coatings tailored to customer requirements.