This review summarizes the more-than-25-years of development of the so-called thermionic vacuum arc (TVA). TVA is an anodic arc discharge in vapors of the material to be deposited; the energy for its melting is delivered by means of a focused electron beam. The resulting material ions fall at the substrate where they form a well-adhesive layer; the ion energy is controllable. The deposited layers are, as a rule, free from droplets typical for cathodic arc deposition systems and the thermal stress of the substrates being coated is low. TVA is especially suitable for processing refractory metals, e.g., carbon or tungsten, however, in the course of time, various useful applications of this system originated. They include layers for fusion application, hard coatings, low-friction coatings, biomedical-applicable films, materials for optoelectronics, and for solid-state batteries. Apart from the diagnostic of the film properties, also the diagnostic of the TVA discharge itself as well as of the by TVA generated plasma was performed. The research and application of the TVA proceeds in broad international collaboration. At present, the TVA technology has found its firm place among the different procedures for thin film deposition.

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Tantalum pentoxide (Ta2O5) thin films were synthesized using thermionic vacuum arc (TVA) technology. TVA is an original deposition method using a combination of anodic arc and electron gun system for the growth of thin films from solid precursors under vacuum of 10−6 Torr. The properties of the deposited Ta2O5 thin films were investigated in terms of wettability, refractive index, morphology, and structure. The surface free energy was determined by means of surface energy evaluation system indicating a hydrophilic character and the refractive index was measured by Filmetrics F20 device. The morphology was determined from bright field transmission electron microscopy (TEM) image performed by Philips CM 120 ST TEM system. It exhibits nanoparticles of 3–6 nm diameter smoothly distributed. Selected area electron diffraction pattern revealed the contrast fringes given by complex polycrystalline particles included in the amorphous film. The measured fringes could be indexed using monoclinic structure of Ta2O5.

The aim of this paper is to report on magnesium plasma diagnostics and to investigate the properties of thin Mg films deposited on Si and glass substrates by using thermionic vacuum arc (TVA) technology. TVA is an original deposition method using a combination of anodic arc and powerful electron gun system (up to 600 W) for the growth of thin films from solid precursors under a vacuum of 10 −6 Torr. Due to the comparatively high deposition rate as well as comparatively high plasma potential-around 0.5 kV-plasma diagnostics were carried out by a heated probe that prevents layer deposition on the probe surface. The estimated value of electron density was in the order of 1.0 × 10 16 m −3 and the electron temperature varied between 4 × 10 4 and 1.2 × 10 5 K (corresponding to two different discharge conditions). The thin Mg films were investigated using SEM images and TEM analyses provided with HR-TEM and SAED facilities. According to the SAED patterns the structure of the films can be indexed as two forms: hexagonal structure for Mg and cubic structure for MgO; the peak value of grain size distribution was 91.29 nm in diameter for Mg TVA/Si and 61.06 nm for Mg TVA/Gl.

Binary elemental plasma of carbon and silver was synthesized using the thermionic vacuum arc technology for the first time in this configuration. The structural investigations of the deposited silver/amorphous carbon (Ag/a-C) nanocomposites thin film on different materials, such as Si, glass, and stainless steel OLC 45 substrates performed by high-resolution transmission electron microscopy were reported, as well as the modification of the properties at the nanometer level.