Ion Beam Sputtering
Ion Beam Sputtering (IBS) is the most advanced deposition technology for the most critical demands on laser optics.
IBS works with RF-guns, typically used for satellite propulsion. Argon ions are accelerated by approx. 1.5 kV onto a metal target. Coating material is sputtered off the target and condenses on a vertically rotating substrate fixture. A uniform coating distribution is limited to an area of about 30 cm in diameter for the standard IBS machines.
Our IBS coating plants have been designed with a secondary RF plasma source. It emits oxygen ions directly onto the substrate surfaces in order to receive well-oxidized, non-absorbing oxide layers.
With the accuracy of LASEROPTIK’s broadband monitoring systems, fractional parts of a monolayer can be detected. As a result of highest precision in film growth and an amorphous, almost defect free microstructure IBS is considered as the most advanced coating technology in today’s thin film industry.
Like magnetron sputtering, IBS is a “cold” process in which the internal temperature does not exceed 150 °C.
The stress can be reduced by compensating layers deposited on the rear surface including additional optical properties, e.g. working as an AR coating.
At LASEROPTIK we actually have 13 machines for special requirements in operation, e.g. high power supermirrors with superior reflectivity (99.99x%) and lowest losses (< 10 ppm), complex filter designs or coatings on crystals. Four of them can work with large optics, so IBS-coatings are available even on substrates up to 2 m in length or Ø550mm (see large optics).
With our GDD measurement setup we also offer dispersive coatings.
Pros and cons of IBS
+ Highest precision, most complex coating designs
+ Lowest losses
+ Excellent microstructure
+ High density
± Stress, can be compensated
– Low deposition rate
IBS coating machine