Simultaneous Measurement of Spatially Resolved Electron Temperatures. Electron Number Densities and Gas Temperatures by Laser Light Scattering from the ICP

摘要

Spatially resolved electron temperatures, electron number densities and gas-kinetic temperatures have been determined at five observation heights, nine radial positions, and two settings of RF input power in an aerosol-free argon ICP sustained with a commercial MAK torch. The measurements were obtained by means of simultaneous ruby-laser Thomson scattering the Rayleigh scattering. In the central channel of the ICP the electron temperature ranges from 7000 K to 8500 K, the gas kinetic temperature is about 1000 K from 1.9 to 7.0 x ten to the 15th power/cc. Among the measured parameters, the electron number density is most sensitive to the input RF power and is noticeable and the Saha equation. The overpopulation-electron recombination processes, resulting in a recombining plasma in the analytical zone. This non-LTE feature might be significant for excitation and ionization mechanisms in the ICP. Keywords: Inductively coupled plasma; Combination diagnostics; Thomson scattering; Rayleigh scattering. (jhd)