Low-power magnetized microdischarge ion source

The authors report on the design and operation of a magnetized microdischarge ion source. The discharge is a coaxial $(E×B)$ configuration with a closed-electron drift. Conditions are selected such that the ions are nonmagnetized and the electrons strongly magnetized. The operating characteristics of this ion source are studied in the $10–40W$ power range, generating a total ion current as high as $0.15A$ and a peak ion energy of $∼150eV$ at an operating voltage of $200V$⁠. The ionization efficiency approaches 100%, although the present design has a fairly large ion beam divergence (⁠$∼80°$ half-angle). The compact nature of this ion source is suitable for localized processing or can be easily clustered for multi-ion processing.