Generation of a low-electron-temperature ECR plasma using mirror magnetic field

The mechanism to generate a low-electron-temperature electron cyclotron resonance plasma using magnetic filed and mixture ratio was investigated by means of simulation and experiment. As the working gas, a mixture of argon and nitrogen was used under the assumption of plasma nitriding. The results showed that the application of the magnetic mirror was valid for decreasing the electron temperature due to both effects of plasma confinement and temperature anisotropy. Furthermore, the addition of nitrogen was found to be effective to decrease the electron temperature approximately 2 eV due to the vibrational excitation of nitrogen molecules by electron impact.