Influence Of Dust On Parameters Of DC Glow Discharge Plasma

Since the discovery of dust particles in space plasma and plasma processing experiments in the 1990 s,dust plasma is now increasingly favored by researchers.Dust particles play a very important role in the application of plasma technology and have a great impact on the plasma deposition and etching in semiconductor processing and the fabrication of thin films and nanoparticles.This is because the charge properties of dust particles after charging will cause changes in plasma environment.Therefore,this paper will use Langmuir probe and emission spectrometry to study the dust plasma in dc glow discharge,and further explore the influence of discharge conditions on dust plasma parameters.Firstly,the dust plasma device and diagnosis system of dc glow discharge are briefly introduced,and the suspension mechanism of dust particles is explained.The characteristic curves of dust plasma probe I-V under different discharge conditions were measured by Langmuir probe.The diagnostic principle of spectral method is expounded,and it is applied to the emission spectrum measurement of dust plasma.Then,the principle of ion density diagnosis by probe is deduced from the cylinder probe model of collision-free sheath.The ion density under different discharge conditions was calculated by using the characteristic curve of probe i-v.Based on the simple cylindrical discharge model,the energy balance equation including dust surface loss term is established,and the relationship between ion density and pressure is numerically simulated.The electron energy distribution function of dusty plasma is calculated by probe curve,and the changes of electron temperature and electron density are analyzed qualitatively.Finally,the theoretical basis of emission spectrum diagnosis of electron density and electron temperature is demonstrated.The electron temperature and electron density of dust plasma under different discharge conditions were calculated by emission spectra.The equilibrium equation of ion number in dusty plasma is established and the relationship between electron temperature and pressure is numerically simulated.According to the theory of orbital motion limitation,the trend of dust average charge with discharge condition is calculated.