Sydorenko S. Pulsed discharge in crossed fields for obtaining coatings with a voluminous surface

Sidorenko S.B. "Pulsed discharge in crossed fields for obtaining coatings with a voluminous surface" – Qualifying scientific work on the manuscript. Ph.D. thesis on speciality for candidate’s degree of technical science 05.27.02 "Vacuum, plasma and quantum electronics". National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", Kyiv, 2021 The dissertation is devoted to obtaining coatings with a voluminous surface using a pulsed discharge in crossed electromagnetic fields. The influence of the pulsed regime of thermoionic deposition on the properties of coatings is considered. The complex way to the development of technological pulse modulators (TPM), their study as part of a plasma generation system and the substance transport process, and the study of the received coatings are shown. A method for obtaining a voluminous surface on an aluminum foil during pulsed ion-plasma deposition of aluminum in an oxygen environment is presented. The dependence of the morphology of the Al O condensate coating from the ratio of oxygen pressure in the vacuum chamber to the deposition rate (PO2/Vс) was determined. It is noted that the specific capacitance of the Al O condensate coating, which was used as a measure of the surface voluminousness, has an extreme character from PO2/Vс and reaches 150 μF/cm2 (while for smooth aluminum foil, the specific capacitance C0 = 0.6 μF/cm2) for PO2/Vс  2,1⋅10 1 Pa⋅min./μm. The discharge of the magnetron sputtering system, the power source of which is the designed TPM was considered. Using diagrams, the development and existence of a pulsed magnetron discharge with and without a preparatory discharge are shown and analyzed. The effect of a pulsed discharge on the coating structure has been experimentally demonstrated. Electric circuits and their models with models of TPM switching elements are presented. The development of pulse modulators, their study as part of systems for pulsed plasma generation during deposition, as well as the study of the obtained coatings, allows to optimize the schemes and operating modes of the TPM and to better understand the processes that occur when a substance is transferred to the deposition object in the technological chamber and on the surface of the coating being created, this, in turn, makes it possible to control the structure of the coating, which was demonstrated in the work. Keywords: coating with voluminous surface, pulse discharge in crossed fields, pulse modulator, ion-assisted deposition, thermoionic deposition, pulsed magnetron sputtering, electron-beam evaporation, specific capacity of capacitor foil.