Compact Plasma and Focused Ion Beams

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Plasma and Wave Diagnostics

Plasma Diagnostics with Langmuir’s Probes

The Langmuir probes have been used as a simple measurement method for

obtaining the local plasma parameters. The technique is well known and has

been discussed in detail by several authors throughout the literature [1–5].

Here we briey summarize the method, its usefulness, and the equations

necessary for determining the plasma parameters. We also present results

of an actual probe characteristic taken from the experiment. The probe mea-

surement method consists of inserting into the plasma a small metallic elec-

trode or probe of known area whose shapes are generally planes, ...