RF impedance measurements of DC atmospheric micro-discharges

TL;DR

This paper introduces a simple, real-time RF-impedance diagnostic method for atmospheric micro-discharges that estimates electron density, demonstrating its effectiveness across different gases and pressures.

Contribution

It presents an inexpensive, real-time RF-impedance technique for diagnosing electron density in micro-plasmas, improving accessibility and ease of measurement.

Findings

Electron density increases linearly with current.

Method provides reasonable estimates for argon and helium micro-plasmas.

Technique is applicable over a wide pressure range.

Abstract

The available diagnostics for atmospheric micro-plasmas remain limited and relatively complex to implement; so we present a radio-frequency technique for diagnosing a key parameter here. The technique allows one to estimate the dependencies of the electron density by measuring the RF-impedance of the micro-plasma and analyzing it with an appropriate equivalent circuit. This technique is inexpensive, can be used in real time and gives reasonable results for argon and helium DC micro-plasmas in holes over a wide pressure range. The electron density increases linearly with current in the expected range consistent with normal glow discharge behavior.