Study of Metal and Ceramic Thermionic Vacuum arc Discharges

The thermionic vacuum arc（TVA）is a new type of plasma source,which generatesa pure metal and ceramic vapour plasma containing ions with a directed energy.TVA dischargescan be ignited in high vacuum conditions between a heated cathode（electron gun）and an anode（tungsten crucible）containing the material.The accelerated electron beam,incident on the anode,heats the crucible,together with its contents,to a high temperature.After establishing a steady-state density of the evaporating anode material atoms,and when the voltage applied is highenough,a bright discharge is ignited between the electrodes.We generated silver and Al;O;TVA discharges in order to compare the metal and ceramic TVA discharges.The electrical andoptical characteristics of silver and Al;O;TVA discharges were analysed.The TVA is also a newtechnique for the deposition of thin films.The film condenses on the sample from the plasma stateof the vapour phase of the anode material,generated by a TVA.We deposited silver and Al;O;thin films onto an aluminium substrate layer-by-layer using their TVA discharges,and producedmicro and/or nano-layer Ag-Al;O;composite samples.The composite samples using scanningelectron microscopy was also analysed.