Hajime Tamagawa

ENERGY DISPERSION OF POSITIVE IONS EFFUSED FROM AN RF PLASMA.

Ion extraction model for plasma-sheath system from an R F plasma and its equivalent circuit are presented. A qualitative explanation of the energy anomalies is discussed. The energy dispersion of ions under the assumption that the ion velocity is modulated by a time variation of plasma potential, is calculated; that is in good agreement with experiments.

PRODUCTION OF LARGE AREA HIGH CURRENT ION BEAMS.

A newly designed microwave ion source has produced with a hydrogen ion beam up to 0.5 A steady state operation with ion energy of 1 keV. The 4 cm diam extraction electrodes are multiple apertures and are arranged in an accel‐decel arrangement. Maximum divergence is 2° from the beam axis. The beam is 85% molecular ions, of which either the diatomic or triatomic component can be maximized by an adjustment of the gas fed to a discharge region. The source is technologically simple, inexpensive, and long lived. The basic concepts underlying the production of ion beams are described.

SOME FEATURES OF AN ELECTRON CYCLOTRON RESONANCE PLASMA PRODUCED BY MEANS OF A LISITANO COIL.

Characteristics of an ECR plasma produced by means of an L-coil are studied in changing the location of exact ECR condition on the coil. It can be seen that the energy distribution function for ions changes from double-humped to Maxwellian, and the quiescent plasma is obtained. Ion compositions of the plasma are measured as a function of electron temperature, and the chemical reactions in the plasma are discussed.