AVS 53rd International Symposium
    Magnetic Interfaces and Nanostructures Tuesday Sessions
       Session MI-TuP

Paper MI-TuP2
RF Atmospheric Plasma Systems for Nanopowder Production and Deposition of Nanocrystallines

Tuesday, November 14, 2006, 6:00 pm, Room 3rd Floor Lobby

Session: Magnetic Interfaces and Nanostructures Poster Session
Presenter: Y. Glukhoy, American Advanced Ion Beam, Inc.
Authors: Y. Glukhoy, American Advanced Ion Beam, Inc.
I. Ivanov, 4 Star, Inc.
Correspondent: Click to Email
Two types of RF atmospheric plasma systems were developed for production of magnetic nanopowder. DC-RF-RF system is supplied by a retrofitted DC plasmatron to convert precursor in powder or aqueous substance into the flow of melted droplets. The DC torch provides a high temperature in the small area in vicinity of the cathode where precursor with a high enthalpy is injected in the discharge through the axial hole. This torch triggers also following atmospheric inductively coupled plasma (ICP) discharge up to self sustaining. So total evaporation and gas-vapor plasma chemical reaction in the fly were implemented in the large high temperature area of the RF reactor where two RF coils at frequencies 13.56 MHz and 27.12 MHz with total RF power up to 18 kW sustain the ICP discharge in the water-cooled 12" long quartz tube with 4.5" OD. The melted droplets were pinched in an axial vapor flow mixed with the process gases. The Laval nozzle at the end of the reactor provides quenching of such a gas-vapor flow and nucleation of mixture in the fly. It simultaneously protects the oil mist that captures the nanoparticles in nanopowder production mode or the polymer substrate in the nanocoating one from the heat flux irradiated by plasma. But production of the ultra-high purity magnetic nanopowder, particularly for drag delivery in the cancer therapy requests the ultra clean technology. We have built a second device where a commercial ICP plasma torch as a melted droplet generator and trigger of the RF reactor was used. The length of the following RF reactor was reduced twice due to the relatively low velocity of the flow. Therefore, just one saddle-like RF antenna that concentrates all RF power inside the inner volume was used in the second stage. Estimation of the atmospheric plasma parameters and of the cooling time in the Laval nozzle is presented. @FootnoteText@Y.Glukhoy, el: Method and apparatus for manufacturing of nanoparticles. US Patent Appl. 20050258149 Nov 24, 2005.