First spectroscopic studies in the plasma-beam installation

This paper presents the results of spectroscopic measurements of plasma in a linear simulator of a plasma-beam installation (PBI) for conducting materials science research. For the first time, non-contact optical diagnostic methods were employed to measure the plasma parameters in the PBI. These measurements were allowed for the clarification of the PBI plasma parameters and the identification of transition zones in different operational modes. Analysis of the plasma emission spectrum enabled the identification of impurity spectral lines and the estimation of key plasma parameters under varying experimental conditions. The spectra were recorded using two optical spectrometers covering a wavelength range of 200–800 nm. The experimental conditions varied in terms of electron beam accelerating voltage (1–5 kV), working gas pressure (1–6 mTorr), and target bias voltage (from −500 to −100 V). The Boltzmann plot method and Stark broadening of the Balmer lines were used to estimate electron temperature and density. Based on the obtained spectroscopic data, the electron density and the electron temperature were determined. The methods described in this study are applicable to linear plasma devices.