BEAM EMITTANCE MEASUREMENTS ON MULTICUSP ION SOURCES

Multicusp ion sources are used for various applications. Presently, th e implementation of this type of ion source is planned for the develop ment of an ion beam lithography machine, which will be used for the pr ojection of sub-0.2 mu m patterns onto a wafer substrate. Since, for t his application, a very good beam quality and a small ion energy sprea d are required, emittance measurements have been performed on a multic usp ion source for various source conditions. It is shown that the ins tallation of proper capacitors between the extraction electrodes is ne cessary to avoid rf pickup, which otherwise leads to a distortion of t he beam emittance. The influence of the magnetic filter field on the b eam emittance has been investigated, and the beam emittance of a de fi lament-discharge plasma has also been compared to that of a rf-generat ed plasma. (C) 1996 American Institute of Physics.