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A low frequency (100 kHz) ferromagnetic enhanced inductively coupled plasma (FMICP) source has been developed to obtain a large volume of dense Cl 2 /Ar plasma. The influence of chlorine addition on the FMICP parameters was investigated both experimentally and numerically using a global (volume averaged) model of Ar/Cl 2 discharge. Radial distributions of the positive ions flux as well as the values of FMICP voltage were measured at a fixed FMICP current of 10 A for molecular chlorine concentrations of 0-4 vol%. Plasma species densities were calculated for various values of chlorine content of 0-4 vol% and absorbed power of 500-2000 W. The calculations showed that chlorine ion density exceeds argon ion density even at low chlorine content of about 0.5 vol%. While experimentally measured discharge voltage and power increased almost linearly up to 3 times with chlorine addition, the experimental and numerical data on plasma density demonstrated only a weak dependence on the discharge power. Thereby, at a fixed FMICP current the discharge power adjusts itself to keep plasma density at the same level even despite a significant change in plasma composition.

An experimental investigation is performed of the electrical and spectral characteristics of plasma of an electrodeless neon light source operating on the principle of inductively coupled discharge. The investigations are performed under the optimal conditions of discharge burning (neon pressure of ~1 torr, current frequency of 250 kHz, and discharge current of 3 to 10 A) corresponding to the high efficiency of the light source (~20%). The spatial distribution of the radiation intensity of individual lines of neon is studied. Measurements are performed of discharge spectra at different points of the gas-discharge bulb and of the electrical characteristics of the discharge. The resultant experimental data are used to calculate and analyze the parameters of discharge plasma (the electron density and temperature and the concentration of excited atoms).

A low frequency (∼100 kHz) distributed ferromagnetic enhanced inductively coupled plasma (FMICP) source with a separate supply of argon and chlorine into the main discharge chamber is proposed in order to obtain a large volume of dense (1010−1012 cm-3) uniform plasma at low pressures (1−100 mTorr). Argon is activated by FMICP sources in U-shaped tubes and diffuses into the main chamber, mixing with chlorine. The Ar/Cl2 mixture is also activated in the main discharge chamber by vortex alternating electric fields circulating in U-tubes and in the chamber. A separate supply of Ar into the side FMICP sources and Cl2 directly into the main chamber can significantly enhance the power transfer efficiency into the main discharge chamber to be used for plasma etching of 450 mm wafers.