Generation of Electron-Beam Produced Plasmas and Applications to Surface Modification
Surface and Coatings Technology
NRL has developed a number of hollow cathodes to generate sheets of electrons culminating in a ‘Large Area Plasma Processing System’ (LAPPS) based on the electron-beam ionization process. Beam ionization is fairly independent of gas composition and produces low temperature plasma electrons (9–1012 cm−3). The present system consists of a pulsed planar plasma distribution generated by a magnetically collimated sheet of 2 kV electrons (/cm2) injected into a neutral background of processing gases (oxygen, nitrogen, sulfur hexafluoride, argon). Operating pressures range from 2–13 Pa with 150–165 Gauss magnetic fields for a highly localized plasma density of ∼1011 cm−3. This plasma source demonstrated anisotropic removal rates of polymeric (photoresist) material and silicon with O2 and Ar/O2/SF6 mixtures, respectively. In pure nitrogen, this same source showed a surface nitriding rate of ∼1 μm/h of plasma exposure time on austenitic stainless steel at 400 °C. Time-resolved in situ plasma diagnostics (Langmuir probes and mass spectrometry) of these pulsed plasmas are also shown to illustrate the general plasma characteristics.
Copyright © 2004, Elsevier
Leonhardt, Darrin; Muratore, Christopher; Walton, Scott G.; Blackwell, David D.; Fernsler, Richard F.; and Meger, Robert A., "Generation of Electron-Beam Produced Plasmas and Applications to Surface Modification" (2004). Chemical and Materials Engineering Faculty Publications. 167.