Image Number 6 for United States Patent #8021489.
A method of forming a plasma to physicochemically modify properties of a fluid spray in a substrate treatment processes includes providing an applicator in proximity to the substrate. The applicator comprises an electrically insulated main body portion containing a cavity, a tube axially positioned within the cavity for transporting a first fluid, an annular electric-field generator positioned within the cavity between the main body portion and the tube, a region between the tube and the generator for transporting a second fluid, and a nozzle connected to the main body portion for mixing the first fluid with the second fluid to form the fluid spray. The tube, the nozzle or the substrate are selectively grounded. Upon activating the electric-field generator, plasma is formed within the tube or about the region between the tube and the generator when the tube is grounded, within the nozzle when the nozzle is grounded or between the nozzle and the substrate when the substrate is grounded.