Inline sputtering system for large area coating

In-situ diagnostics and model-based control of in-line magnetron sputtering processes for large-area coating.
© Fraunhofer IST, Rainer Meier, BFF Wittmar

In-situ diagnostics and model-based control of in-line magnetron sputtering processes for large-area coating.

Beispiel einer Low-E-Beschichtung auf Glas. Typischer Aufbau eines Einfach-Silber-Schichtsystems für ein vorspannfähiges Schichtsystem.
© Fraunhofer IST

Beispiel einer Low-E-Beschichtung auf Glas. Typischer Aufbau eines Einfach-Silber-Schichtsystems für ein vorspannfähiges Schichtsystem.

Modular system

At the Fraunhofer IST the Leybold A700v inline sputter coating system is available for coating glass, plastic or metallic substrates in a size range from 5 x 5 cm2 to 60 x 100 cm2. The system consists of a total of seven chambers, including two sluice chambers for fast loading and unloading. Each coating module includes a sputtering station that can be equipped with a maximum of two different targets. Through this measure it is possible to handle up to 10 different materials at the same time and thus it is also possible to produce complex coating systems.

The substrate is introduced via a clean room, in which a commercial substrate cleaning system is located. Cleaning occurs in a section of acid and alkaline baths and a deionized water basin, in which the substrates can be treated with ultrasound.

 

A variety of sputtering processes

The system allows work with all common, but also with some special sputtering processes:

  • DC (Direct current )
  • DC pulse
  • MF (Mid frequency)
  • RF  (Radio frequency)
  • RF+DC (DC overlaid RF sputtering)
  • HIPIMS (High Power Impulse-Magnetron-Sputtering)
  • MF+ HIPIMS
  • Megatron®

In this regard, the sputtering can be either direct from the ceramic target or reactive. As reactive gases oxygen or nitrogen are used but hydrogen and other gases are also possible. Monitoring and control of the reactive processes with oxygen occurs via lambda sensors, which are integrated in a PID power regulation unit in order to set the desired oxygen partial pressure.

As a rule, process control occurs dynamically, however depending on the task, static coatings are also possible. The layer thickness is set by the selected power and the carrier speed. A transport system controlled via stepper motor allows high accuracy. Sequence and reproducibility are guaranteed by programs that can be freely created. The system can be operated at temperatures up to 400 °C.

Application areas

  • New transparent conductive oxides (TCOs)
  • Active semi-conductive oxides (ASOs),
  • Low-e coatings 
  • Interference optics
  • Electrochromism 

Materials 

A variety of metallic and ceramic target materials are available for different applications. Depending on the process, corresponding metals, oxides, oxynitrides and nitrides can be deposited. Furthermore, the coating module Megatron®, which is also developed at the Fraunhofer IST, allows to mix different materials. The following coating materials are available at the Fraunhofer IST:

Coating materials FORMulars
Silver, silver doped with aluminium, silver doped with titanium Ag, Ag:Al, Ag:Ti
Aluminium, aluminium oxide, aluminium nitride Al, Al2O3, AlN
Bismuth doped with manganese, bismuth oxide doped with manganese Bi:Mn, Bi2O3:Mn
Chromium, chromium nitride Cr, CrN
Indium oxide doped with tin (5 or 10 wt % SnO2 within sputter target) In2O3:Sn 
Copper, copper oxide Cu, CuO
Magnesium, magnesium oxide Mg, MgO
Nickel chromium Ni:Cr 
Niobium, niobium oxide, niobium nitride Nb, Nb2O5, NbN
Nickel vanadium NiV
Silicon, silicon oxide, silicon nitride Si, SiO2, Si3N4
Silicon doped with aluminium (10 wt% aluminium), silicon aluminium oxide, silicon aluminium nitride  Si:Al, SiAlOx, SiAlNx
Tin, tin oxide Sn, SnO2
Tin doped with antimony, tin oxide doped with antimony Sn:Sb, SnO2:Sb
Titanium, titanium oxide, titanium nitride Ti, TiO2, TiN
Vanadium, Vanadium nitride V, VN
Tungsten, tungsten oxide, tungsten nitride W, WO3, WN
Zinc, zink oxide  Zn, ZnO
Zinc doped with aluminium (0,3 till 1,75 wt% aluminium) Zn:Al
Zinc oxide doped with aluminium (various aluminium doping concentrations) ZnO:Al
Zinc doped with gallium (0,5 till 1,0 wt% gallium) Zn:Ga
Zinc oxide doped with gallium ZnO:Ga
Zinc tin oxide (various Zn:Sn atom proportions: 50:50 till 68:32) ZnSnOx
Zinc tin gallium oxide (Zn:Sn:Ga atom proportion: 62:30:8) ZnSnGaOx
Zirconium doped with yttrium, zirconium oxide doped with yttrium  Zr:Y, ZrO2:Y


If required, further target materials can also be ordered.