Electron Kinetics in Low Pressure Plasmas

Low pressure plasmas are widely used in the semiconductor industry in the manufacture of integrated circuits both for anisotropic dry etching and for the deposition of materials. They are characterized by a pronounced non-equilibrium between very hot electrons (~30,000-50,000 K) and the much colder gas atoms and ions (~300-2000 K) in the plasma. Our group is involved in detailed experimental and theoretical studies of the energy distribution function of electrons, which often strongly deviates from an equilibrium distribution (Maxwell-Boltzmann distribution). Our studies focus both on the spatial variation of this distribution function in strongly non-uniform plasmas and the temporal variation in pulsed plasmas.

Representative publications:
“Experimental study of diffusive cooling of electrons in pulsed inductively coupled plasma,” Antonio Maresca, Konstantin Orlov, and Uwe Kortshagen, Phys. Rev. E 65, 056405 (2002), DOI: 10.1103/PhysRevE.65.056405.

“Recent progress in the understanding of electron kinetics in low-pressure inductive plasmas,” U. Kortshagen, A. Maresca, K. Orlov, and B. Heil, Appl. Surf. Sci. 192 , 240 (2002), DOI: 10.1016/S0169-4332(02)00028-4.

Temporal evolution of the electron energy distribution function in the afterglow of a pulsed inductively coupled plasma.