Institute of Fluid-Flow Machinery
Polish Academy of Sciences

Abstract

In this paper we present a simple and cheap microwave (2.45 GHz) source of microdischarges in argon and neon at atmospheric pressure. The source consisted of cheap 2.45 GHz microwave magnetron generator and 50 Ω coaxial line terminated with a simple coaxial plasma applicator. The new microwave source of microdischarges operated stable in the form of a small plasma jet at absorbed microwave powers of 9-80 W and gas flow rates of 0.5-0.25 l/min. The length and diameter of plasma jets were 1.5-14 mm and 0.5-1.5 mm, respectively, depending on the kind of gas, gas flow rate and microwave power absorbed by the discharge. The temperature of the plasma jets could be changed from 30°C to 1200°C by changing the gas flow rate or/and absorbed microwave power. The electron density in the plasma jet was around 3 ⋅ 10¹⁴ cm^-3 – 1.1 ⋅ 10¹⁵ cm^-3, depending on the discharge conditions.