Measurements of Energy Distributions in ECR Plasma

Abstract

The electron energy distribution is measured in an ECR device for H 2 and N 2 plasmas as a function of pressure. The maximum measurable energy and the high-energy tail increase with decreasing pressure. However, the energy distribution at the high-energy part progressively departs from a Maxwellian shape as the pressure is increased. The electron temperature obtained from the low-energy part increases with decreasing pressure. The positive ion temperature is of the order of a few eV and increases with the electron temperature. A mechanism of ion acceleration should exist.