Floating harmonic probe for diagnostic of pulsed discharges

Abstract

The floating harmonic probe (FHP) is a relatively new plasma diagnostic method for electron temperature and positive ion density measurement, which can be used in conditions when insulating films are being deposited on the probe and, consequently, the classical Langmuir probe method fails. Recently an extension of this method called PDHAM – phase delay harmonic analysis method - was proposed that is applicable also to pulsed discharges. In this contribution, we study the possible limitations of this new method and present the comparison of the plasma density and the electron temperature determined by PDHAM with that obtained by the time-resolved Langmuir probe in a pulsed planar magnetron discharge. In addition, we present the double probe technique for applications in pulsed plasmas and we compare its results with those of a single FHP. The experiments were performed in argon at pressures several Pa in a non-reactive regime, when no insulating film was deposited on the probes.