The deposition conditions during reactive magnetron sputtering of metal nitrides can not only influence the particle flux towards the substrate but also the energy and momentum flux. As the variation of one of these fluxes could influence the thin film growth, characterization of these fluxes is an important step towards modelling of the thin film growth.
The following approach is used to characterise the particle flux. First, the transport of sputtered particles from the target towards the substrate is modelled by Monte Carlo simulation. Secondly, energy resolved mass spectrometry is used to identify all particles and to analyze the plasma composition as a function of the used deposition conditions. With these measurements it is possible to characterize the particle flux. Finally, by means of Langmuir probe measurements, the plasma properties such as the electron and ion density, electron temperature, and plasma potential were measured.
Knowing these plasma properties, the energy and momentum flux due to electrons and ions can be calculated. Together with the other mentioned measurements, the total fluxes towards the substrate, during reactive magnetron of TiN are calculated. The influence of the target-substrate distance, the Ar/N2 gas flow ratio and the magnetic balance of the magnetron on these fluxes will be discussed.
A further step is to link these fluxes to the thin film growth. Hence, TiN films were deposited at the same deposition conditions of the discussed measurements. The intrinsic properties of these thin films, i.e. their stoichiometry, microstructure and crystallographic orientation are characterized by electron microscopy, energy dispersive X-ray analyses and X-ray diffraction. To evaluate the mechanical properties of these films the hardness was measured by nanoindentation.
This full characterisation of the deposited films opens the possibility to find out fundamental relationships between i) the energy flux, the momentum flux and the particle flux; ii) the intrinsic properties and iii) the mechanical properties of transition metal nitrides deposited by reactive magnetron sputtering. These fundamental relationships form an ideal test case of the modelling of thin film growth.
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