Continuum double probe theory: effects of electron emission due to metastable species de-excitation and unequal probe arm saturation currents

Abstract

Examines theoretically two different effects which are sometimes encountered in double probe measurements under continuum large-Debye-length conditions: (i) electron emission due to the de-excitation of metastable atoms and molecules on the probe surface, and (ii) asymmetric double probe characteristics that result from number-density gradients on the plasma. Electron emission is shown to have little effect on the probe characteristics. A method of analysing asymmetric double probe characteristics is discussed.