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The pulsed i-PVD technique High Power Impulse Magnetron Sputtering (HIPIMS) was used to study the effect of adspecies flux, i.e. inert gas and depositing flux, on the texture and structure evolution in titanium nitride (TiN) thin films. The TiN depositions were carried out onto silicon substrates in an Ar/N2 atmosphere at ambient temperature and TS=400°C, both without and with applied negative substrate bias (Ub=0–100 V) by sputtering from a Ti target. The deposited thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The stress was measured in-situ during film growth. The chemical composition of the films was determined by elastic recoil detection analysis (ERDA). Detailed investigation of the particle fluxes (energy- and time-resolved) to the growth surface was performed using a mass spectrometer with an energy filter. The measurements revealed a shift of the center of mass of the ion energy distribution from higher energies (~20-30 eV) to an energy corresponding to that of thermalized ions as the pulse proceeds. Even several 100s of μs after the pulse was turned off, metal as well as gas ions could be detected. At ambient temperature random out-of-plane oriented films with clearly faceted grains developed, due to energetic bombardment leading to knock-on events and continuous renucleation. An increase of the deposition temperature (TS=400°C) resulted in smooth surfaces without any facets and with different preferred out-of-plain orientations depending on the level of substrate bias applied. At high pressures, i.e. as the high energy tail of the depositing species was reduced, {111} out-of-plane PO was observed, whereas an increased pulse length led to a {002} out-of-plane PO. From these results a growth model for HIPIMS has been developed explaining the dense microstructure achieved with HIPIMS even at ambient temperature and without applied substrate bias.
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