Performance test of high brightness nano-aperture ion source

Abstract

The nano-aperture ion source (NAIS) is a candidate to be part of a compact proton beam writing system, which has the potential of high throughput with sub 10nm spot sizes. To evaluate the performance of this ion source, different NAIS chip configurations were examined through simulation. This study suggests that a proton reduced brightness of more than 106A/(m2srV) can be achieved, with an ion energy spread of less than 1eV. Meanwhile, a prototype NAIS has been fabricated and tested to deliver 800A/(m2srV) of reduced brightness for Ar+ beam. Current limitations and further improvements of this prototype NAIS are discussed.