AG Hofsäss - II- Institute of Physics

Mass selected ion beam deposition (MSIBD) is the most precise and well-defined method to grow specific thin film coatings and investigae the dependence of film properties and film structure on the ion energy an ion species deposited. However, the growth rate is low and typically the deposition has to be done under Ultra-High-Vaccujm conditions to avoid unwanted contaminations of the films.
We have build a unique MSIBD System based on an conventional ion implanter with multi-purpose hollow-cathode hot-filamnt ion source. We start with a 30 keV mass selected ion beam which is decelerated in a UHV chamber to verly energies down to 10 eV. The ions are then deposited on a chosen substrate. The deceleration is quite efficient and uniform over abour 2.5 cm² with ion current on the substrate up to about 20µA, depending on the ion species.
The MSIBD system is connected to a sample load lock system as well as an attached UHV-chamber for Auger spectroscopy and photoelectron spectroscopy.

With this system we have extensively investigated the growth of diamond-like tetrahedral amorphous carbon (ta-C) which efficiently forms at 100 eV ion energy. We have also studied the growth of cubic boron nitride (c-BN) thin films and have established a phase diagram for nucleation and growth of this ultra hard material. We have also synthesized various diamond-like compund films such as carbon nitride, fluorinated amorphous carbon, boron carbide and metal carbon nanocomposite films.

Currently the MSIBD system is mainly used for ultra-low energy ion implantation into graphene and other 2D materials such as MoS₂. Avaialle dopant ions are B,N,P,F,S,Se,W and mayn others.