LANGMUIR PROBE TO CHARACTERIZE THE DUST PLASMA OF ALUMINUM OXIDE (AL2O3) PRODUCED BY DC PLASMA SYSTEM
In this research, we have conducted an experimental study of the dusty plasma to the Aluminum oxide (Al2O3) dust material with a grain radius of (0.2) µm to (0.6) µm. In the experiment, we use air in the vacuum chamber system under different low pressure (0.1-0.8) Torr. The results have showed that the existence of dust particles in air plasma is equal to the Paschen minimum which is (0.4) Torr with Al2O3 dusty and without dust. The effect of Al2O3 dust particles on the plasma characteristics like floating potential (Vf), plasma potential (Vp), electron saturation current (Ies), temperature of the electron (Te), density of electron (ne) and density of ion (ni) of the DC system that can be calculated in the glow-discharge region. Parameter measurements are taken by four cylindrical probes which are diagnosed at a distance of (40) mm from the cathode diameter, the Paschen minimum at a pressure of (0.4) Torr. The plasma potential and the probe's floating voltage become more negative when dust is immersed in the plasma region. The features of these parameters show that the current discharge decreases while the discharge voltage increases when the aluminum oxide dust particles that are incorporated. And vice versa was in the absence of dust. Electron density increases in the existence of dust particles which causes the electron temperature to decrease.
Keywords: Plasma Parameters, Langmuir Probe, Properties of Aluminum Oxide Dust, Plasma Diagnostics, Glow Discharge, Paschen Curve