Abstract：In this paper, the preparation and experimental diagnostic of low-pressure and low-temperature non-equilibrium plasma in industrial production and military applications are investigated. A one-dimensional fluid model of capacitive coupled RF plasma discharge is established by using the COMSOL software plasma module. The axial distribution of electron number density and electron temperature under different pressures and different voltages are calculated taking Helium as working gas. The electron density ne and electron temperature Te are also calculated according to the equivalent circuit of uniform RF discharge by building a plasma generation and diagnosis platform. The results show that when the gas pressure is 100~250Pa, the electron density increases first and then decreases along the axis, the electron temperature reaches the minimum at the center of the electrodes. There are two peaks in the edge of the electrodes, and the average electron temperature is only a function of the pressure and the size of the cavity. With the increase of input power, the electron density increases from gradually to rapidly, and this jump of electron density appears in different voltage amplitudes at different pressures, which indicates the α -γ transition in capacitively coupled discharge. The experimental diagnostic is consistent with the results of COMSOL simulation. The conclusions expand the application range of simulation and experiment for fast non-interference diagnosis, which is useful for further study on low-temperature plasma discharge.
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2019, Vol. 34 
