Characteristics of a partial-coaxial cavity-type holey-plate ion source

A low-pressure and high-density microwave ion source, created and sustained by evanescent waves emitted from a holey plate, and using a partial-coaxial cavity resonator, has been newly developed for the production of stable beams from gaseous feed materials. This source is called a holey-plate ion source. A microwave of 2.45 GHz is supplied from a coaxial cavity and then converted into an evanescent mode through the use of a holey-plate. The plate is made from a 0.5 mm thick, 54 mm diameter stainless steel sheet with 2.5 mm diameter, 3.6 mm pitch holes, thus allowing high-density plasma to be generated near the surface of the plate. A detailed source description and beam properties are presented in this paper.