Electron Kinetics in Gas Discharges

Gas discharges present an example of extremely non-equilibrium systems. This property comes from a large difference between the mass of electrons and the mass of atoms and molecules. Due to the great distinction of mass, the energy exchange in elastic collisions between electrons and gas molecules is inefficient, and the application of electric fields results in electron heating up to energies of a few eV (30,000K) comparable to ionization potential of atoms (with gas remaining at the room temperature). Low temperature plasmas (LTP) of gas discharges are characterized by low ionization degree of 10-6-10-3 and electron temperatures two orders of magnitude larger than gas temperatures. The electrons produce exotic chemical reactions not possible in equilibrium systems. These LTPs are widely used in many modern technologies including semiconductor manufacturing (etching and deposition of computer chips), lighting, plasma display panels, etc. We will present examples of electron kinetics in different plasma sources, describe intriguing physics of self-organization at the kinetic level for ionization waves (striations) in Direct Current discharges, and describe state-of-the-art modeling and simulation of electron kinetics in LTPs.

Dr. Vladimir Kolobov, Manager of Plasma Technologies at CFD Research Corporation, obtained his PhD degree in 1989 from the Leningrad State University in Russia. From 1990 to 1991, he worked as a Senior Research Scientist in the Institute of Hypersonic Velocities and taught at St. Petersburg University in Russia. In 1992-93, he was a Visiting Scientist in the Laboratoire des Discharges dans les Gaz, Universite P.Sabatier, in Toulouse, France. He worked as a Research Associate in the Engineering Research Center for Plasma-Aided Manufacturing at the University of Wisconsin in Madison in 1994-95, and in the Plasma Processing Laboratory at the University of Houston in 1995-97. Dr. Kolobov joined CFDRC in October 1997 and has been responsible for the development of plasma technologies and kinetic methods at CFDRC. He was a key architect of the first commercial software, CFD-PLASMA, for simulations of plasma devices and processes. He was a PI of several multi-year SBIR projects from NSF, DoD, NASA, and numerous industrial R&D projects from GE, Samsung, TEL, Panasonic, MKS Instruments, ABB, Inficon, and other companies. Dr Kolobov is an expert in theoretical and computational plasma physics, physical kinetics, CFD and rarefied gas dynamics, the author of over 50 journal articles and numerous conference presentations.

Vladimir Kolobov

CFDRC