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arXiv · 1406.5632

Computerized Langmuir Probe Measurements in a Capacitively Coupled RF Discharge

M. El Shaer·A. S. Mohamed·A. Massoud·M. Mobasher·M. Wuttmann
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Abstract

A system of automated computerized Langmuir probe measurements is used in order to determine the plasma parameters in a plasma reactor constructed for cleaning of metallic artifacts by RF discharge. A compensated probe insures the suppression of the RF interference. The probe data are collected using a commercial data acquisition unit connected to a portable computer. The raw data are processed using wavelet transforms techniques which assures the de-noising of the probe signal without distortion of the probe I-V characteristic. The first and second derivatives of the I-V characteristic are determined. The measurement of the electron density spatial distribution in the inter-electrode distance indicates a flat density profile in the middle region of the discharge.

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M. El Shaer, A. S. Mohamed, A. Massoud, M. Mobasher, M. Wuttmann. 2014-06-21. Computerized Langmuir Probe Measurements in a Capacitively Coupled RF Discharge. https://arxiv.org/abs/1406.5632

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