Thermionic Vacuum Discharges for Thin Film Depositions

Abstract

The thermionic vacuum discharge method is very effective in that the films obtained using this technology are characterised by a very high degree of adhesion, density and purity because the deposition technique is carried out in high, very high or, if possible, in ultra-very high vacuum conditions with no gas present. When the substrate is placed in vacuum, no heat transfer particles are present, the substrate being heated only by the ion incident on the surface. This advantage recommends the TVD method for deposits on plastics or other thermally sensitive materials. Additionally, this slow heat transfer reduces energy loss, making the deposition method industrially competitive. The paper aims to present theoretical aspects of this type of discharge, compared to typical or more popular plasmas but also to present the achievements of this method and its utility in the thin films production, layers that have specific imposed properties. The practical depositions and applications presented are in the nuclear fusion-related material science and also for obtaining materials for granular structures, used as magneto-resistive coatings.

Analysis and Optimization of Contact Material Ablation under the Cumulative Effect of the Number of Breakings of OLTC

“…Since the contact resistance constitutes a significant proportion of the circuit resistance within the interrupter chamber, the temperature rise in OLTC is significantly influenced. Contact resistance is composed of both shrinkage resistance and surface film resistance, with the value of the surface film resistance experiencing an increase [ 21 , 22 ]. The formula for calculating the surface film resistivity is as follows: …”