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The aim of the present paper has been to verify the effectiveness and usefulness of a novel deposition process named GIMS (Gas Injection Magnetron Sputtering) used for the first time for deposition of Ti/TiO2 coatings on large area glass substrates covered in the condition of industrial scale production. The Ti/TiO2 coatings were deposited in an industrial system utilizing a set of linear magnetrons with the length of 2400 mm each for covering the 2000 × 3000 mm glasses. Taking into account the specific course of the GIMS (multipoint gas injection along the magnetron length) and the scale of the industrial facility, the optical coating uniformity was the most important goal to check. The experiments on Ti/TiO2 coatings deposited by the use of GIMS were conducted on substrates in the form of glass plates located at the key points along the magnetrons and intentionally non-heated during any stage of the process. Measurements of the coatings properties showed that the thickness and optical uniformity of the 150 nm thick coatings deposited by GIMS in the industrial facility (the thickness differences on the large plates with 2000 mm width did not exceed 20 nm) is fully acceptable form the point of view of expected applications e.g. for architectural glazing. [ABSTRACT FROM AUTHOR]

Abstract: The paper describes the very first observations of the effect of pulsed gas injection to the coaxial accelerator during impulse plasma deposition (IPD) on the structure and properties of deposited material. As a test material a TiN coating deposited on high-speed steel substrates was chosen. The morphology and wear-resistance properties were determined. The structure obtained with modified IPD method is characterized by a crystalline structure built of rectangular nanograins (with size a few tens of nm) in contrast to the nanocrystalline structure based on three-dimensional (3D) agglomerates of nanoparticles typical for the standard IPD synthesis. The wear-resistance of the TiN coatings deposited in the modified IPD apparatus demonstrate very good properties with the best results more than ten times better compared with the uncoated steel substrates. [ABSTRACT FROM AUTHOR]

Abstract: In this work we investigated the mechanism of growth of the coatings produced under various conditions of the Impulse Plasma Deposition (IPD) process. The deposition of the coating material in this method proceeds on the non-heated substrate. Creation of the coating consists of a surface migration of the clusters which were formed in the plasma itself, fallowed by their uncompleted coalescence. We proved that various thermal conditions of the coating/substrate system could dramatically change the mechanism of coating formation. Some differences in the mechanism of the coating growth result in the radical change of its structure from the compact and homogenous to the strongly anisotropic. Additionally, we suggest a presence of supplementary process that participates in the coating creation that proceeds out of the main process of the deposition from the impulse plasma. [Copyright &y& Elsevier]

In surface engineering impulse plasma is used in the synthesis and deposition of various materials in the layer form. Within the impulse plasma deposition (IPD) coaxial accelerator plasma is generated in the working gas due to a high-voltage high-current pulse discharge. In the present study the influence of accelerator geometry on the Rayleigh–Taylor instability formation behind the front faces of the electrodes has been analysed both computationally and experimentally. Structure of the plasma in this region is very important for the quality of the coatings produced, thus the presented findings increase the understanding of processes relevant for the IPD technology. [Copyright &y& Elsevier]

Abstract: The paper describes the effects of utilizing pulse valves for dosing a plasma forming gas supplied directly to the plasma source. The concept of exploiting such valves as actual controllers of the plasma process replacing the ignitrons–spark switch valves used up to now has been practically verified in the technology of TiN layers manufactured by impulse plasma deposition (IPD) method. The TiN layers manufactured at modified plasma pulse generation conditions on unheated cutting tools made it possible to increase the cutting lifetime by a factor of up to twenty. The interpretation suggests that this increase is likely to result from lower energy dissipation for intermolecular collisions because of an increased mean free path. On the basis of positive results of research related to IPD method, the method of plasma excitation through an injection of plasma-forming gas has been applied in conditions of magnetron sputtering (gas injection magnetron sputtering, GIMS). GIMS applied as a material source with a single magnetron has been used for formation of AlN layers on silicon substrates. Electronic examination of MIS structures with such thin AlN layer demonstrated potentially advantageous structural properties of such layers in the context of their application in the design of electronic devices, e.g. as gate insulator layers. [Copyright &y& Elsevier]

The article presents the results concerning the OES characterization of plasmoids generated by the Impulse Plasma Deposition method modified by the use of gas injection (Gas Controlled IPD). Both of the electrodes of the coaxial accelerator: the tube (cathode) and the rod (anode–the source of the vapors) are permanently connected with the capacitors charged to the high voltage of few kV value. During the coatings deposition both the electro-eroded vapors of the anode material (Ti) and the working gas (N 2 ) form the plasmoids which are accelerated by the Ampere force in the coaxial accelerator and ejected to the vacuum chamber in the direction of non-heated substrates forming there the TiN coating. Periodic gas injections which make pressure fluctuations in the accelerator space in the range of critical values and cause the discharge to initiate or vanish accordingly with the chosen frequency. The promising practical effects of the use of gas injection for controlling the plasma processes during the coatings deposition by the GCIPD method was previously proved. On the basis of the present studies one can state that the GCIPD′ plasmoids containing multiple ions both of metallic as well as gas plasmoids constituents are more energetic as compared to the IPD case. Contrary to the IPD during the GCIPD the titanium fraction of the plasmoids structure overtakes the nitrogen one which seems to be important to the coating growth mechanism. [ABSTRACT FROM AUTHOR]

Abstract: In this work we present the results of studies that compare the structure of coatings obtained by the Impulse Plasma Deposition (IPD) method with two different frequencies of generation of plasma impulses. As a control material the TiN coating was chosen. The morphology and topography of the layers were characterized by means of scanning and transmission electron microscopies (SEM, TEM). Results of our investigation showed that an increase in the frequency of plasma generation from 0,25Hz to 4Hz enhanced the more intensive agglomeration and crystallization processes. Additionally the increase in number of plasma impulses in the case of the HF IPD process was accompanied by an increase of the number of agglomerates without visible changes in dimensions. [ABSTRACT FROM AUTHOR]

This paper reports the results obtained from the deposition of diamond-like carbon (DLC) films on glass substrates by gas injection magnetron sputtering method. The conducted studies aimed to evaluate if the plasma discharge that is generated by varying the proportions of neon−argon (Ne−Ar) gases during pulsed injections (0%–100%) would promote the synthesis of DLC films with desirable sp3 phase by means of electron impact-induced plasma interactions. The obtained DLC films showed the presence of sp3 (C C) hybridized bonds along the Gaussian distribution curve, which revealed that a maximum sp3 content in the range of 32%–45% was obtained along the 40% injection of Ne gas, based on the analysis of the C1s core-level spectra and Raman spectroscopy. A 25% gain in hardness (H) and resistance to cracking (H3/E2) were also observed in the sp3-rich DLC sample (24.1 ± 4 GPa and 0.29 ± 0.04), thus promoting its use in various nanomechanical systems. The change in the sp3/sp2 fraction ratio, demonstrated in this research, corresponded well to a calculated model of graded optical bandgap in the range from 0.53 to 3.01 eV. However, to further minimize the parasitic reflectance from a significant share of sp2 (C=C) domains, thin titanium dioxide (TiO 2) (8–36 nm) layers were deposited on the DLC surface, which provided maximum antireflective effect due to interference shift. A significant increase in visible–near-infrared transmittance (up to 87%) was observed as a result of such an interference in DLC/TIO 2 bilayers. Our results have practical applications and aid in the design of functional nanocoating structures which are tremendously favored and required to improve the toughness of commercially available glass protectors in hostile environmental conditions. [Display omitted] • Diamond-like carbon films were deposited using an impulse magnetron sputtering method. • Injection of neon within the gas mixture, promoted nucleation of sp3 phase, up to 45%. • The richest sp3–bonds DLC film revealed a graded energy band gap from 1.17 to 3.01 eV. • The transmittance of the single carbon layer (~65 nm) was ~70% in the visible range. • 8–nm–thick TiO 2 upper film brightened the bilayer structure, up to 87% in the Vis–NIR. [ABSTRACT FROM AUTHOR]

This paper presents the effects of a power pulse delay with regard to a gas pulse generated in the Gas Injection Magnetron Sputtering (GIMS) technique. The GIMS technique is a variant of magnetron sputtering, in which the gas pulses control plasma. During the deposition of a coating, the pressure oscillates between the threshold values, initiating and terminating a discharge. In this work, the power pulse was considered as the second parameter of plasma control over the gas pulse. In our opinion, the state of plasma dynamically changes during the gas pulse period, which was studied using optical emission spectroscopy. The largest population of excited atoms of the sputtering gas was detected in the first stage of the gas pulse, while the highest number of ions was observed in the middle stage and the smallest population of plasma constituents in the end stage. The next step of the study involved examining the structure and phase state of the TiO 2 coatings deposited when plasma was generated in various stages of the gas pulse. The structure of the coatings strongly depended on the deposition conditions, such as pressure and plasma content. The coatings were characterized by an amorphous structure that crystallized in rutile form under bombardment by energetic plasma species. The depth of crystallization was influenced by the content of plasma in a particular stage of the gas pulse. During the last stages of the gas pulse, very thick coatings were obtained in the deposition process. Moreover, the coatings exhibited metallic features. In such a condition, it can be expected that there will be no sputtering in reactive gas mixture, and the magnetron might operate in the self-sputtering mode. Thus, this work showed that delaying the power pulse with regard to the gas pulse would help to optimize the features of the deposited coating material. [ABSTRACT FROM AUTHOR]