Development of a low temperature plasma source providing ion flow energy control

A low electron temperature plasma source suitable for control of ion flow energy along magnetic-field lines is developed, which is made up of an ion-production region and a plasma-synthesis region. A mesh-shaped electron emitter is installed in order to uniformly supply the electrons to the synthesis region. Our diagnoses using Langmuir probes and electrostatic ion energy analyzers prove that only the ion flow energy can be controlled under constant electron density and temperature. Moreover, our method is found to achieve a low electron temperature (T_e ≃ 0.2-0.4 eV), yielding almost uniform radial and axial profiles of the averaged electron density, temperature, space potential and the ion flow energy.