info@kosartech.com
Author: Ali Kosari Mehr
An anode spot or a fireball is a phenomenon in which a high potential plasma emerges at an electrode surface being at a relatively higher positive bias than the potential of the bulk plasma. This high potential plasma is generated by the outward movement of a double layer (i.e., a structure consisting of two parallel layers of opposite electrical charge in plasma); the double layer is created owing to the sufficient electron impact ionization rate of neutrals near the electrode.
The deployment of this phenomenon for assisting the sputtering process was proposed by Kosari Mehr; this method was coined ‘anode-spot-assisted sputtering (fireball-assisted sputtering)’. Accordingly, the main application of this novel method is to utilize the high-potential, dense plasma of an anode spot as a secondary plasma for considerably ionizing sputtered/neutral atoms near the substrate and for the possibility of simultaneously depositing sputtered species and products produced as the direct result of introducing dust into the dense plasma.
The introductory configuration proposed for this deposition method consists of three magnetron sources—the larger one (i.e., sputter gun) acts as the cathode and the smaller ones function as the anodes (i.e., inverted guns)—a hollow/transparent grid, a substrate holder, anode shields, a large chamber, power sources, gas inlets, and pump outlet. In this configuration, the anode spot generated in the region where the inverted guns are placed can be used as an ion source or an ionizing column for neutral species entering the region.
For further information regarding this method and its schematic configuration, please use this Link.
