Atomistic view on thin film nucleation and growth by using highly ionized and pulsed vapour fluxes

Abstract

We present a brief review on the use of ionized and pulsed vapour fluxes, primarily generated by high power impulse magnetron sputtering (HiPIMS) discharges, as tools to gain atomistic understanding on film nucleation and growth. Two case studies are considered; the first case study concerns stress generation in polycrystalline films. It is highlighted that by using vapour fluxes of well-controlled ion content and ion energy and by studying the film microstructure and intrinsic stresses one can obtain experimental evidence for stress generation by insertion of film forming species in the grain boundaries. In the second case study it is discussed how the use of pulsed vapour fluxes with well controlled time domain can facilitate understanding of growth dynamics and microstructural evolution in thin films grown in three-dimensional (i.e., Volmer-Weber) fashion. Broader implications of the described research strategies for the surface science and surface engineering communities are highlighted and discussed.2

Influence of ionisation zone motion in high power impulse magnetron sputtering on angular ion flux and NbOxfilm growth

“…The beneficial effects of ion bombardment for the growth of thin films using physical vapour deposition in general [46][47][48][49][50] and HiPIMS in particular [51][52][53] have been described in great detail. For the current work, we mainly limit the discussion to effects related to the angular ion fluxes.…”

An Overview on Time‐Resolved Optical Analysis of HiPIMS Discharge

“…Historically, both intrusive (mainly represented by Langmuir probe measurements and energy‐resolved mass spectrometry) and non‐intrusive (mainly optical spectroscopy‐related) plasma characterization techniques have been used during the last two decades, which certainly increased our level of understanding of the HiPIMS discharge processes . The mentioned research work most of the time has been followed by the corresponding technological developments, such as enhancement of the deposition rate, improved control of the film microstructure, low‐temperature deposition, including deposition on polymer substrates, etc. Numerous studies related to the magnetron discharge characterization, dealing with both non‐reactive and reactive HiPIMS discharges, have to be acknowledged in this context …”

Phase separation within NiSiN coatings during reactive HiPIMS discharges: A new pathway to grow NixSi nanocrystals composites at low temperature

“…At low N content (between 0 and 16 at.%), both Ni and Si ad-atoms can diffuse on the surface of the substrate, encounter another adatom and form clusters which then serve as a sink for the subsequent stages of film growth including island nucleation and growth, impingement and coalescence of islands and development of a continuous film. 47,48 Compositional inhomogeneities within the film are unlikely due to the fact that Ni and Si are fully miscible. 49 A calorimetric investigation 50 as well as thermodynamic modeling of the Ni-Si system [51][52][53] report the solid solubility of Si in the fcc phase of Ni at about 10 at.% Si.…”