Multicusp ion source for ion projection lithography

The need to extend to smaller and smaller features (sub-100 nm) in integrated circuits has created the necessity to investigate new technologies beyond optical lithography. Ion projection lithography (IPL) is an advanced lithographic concept that can provide the solution for the high volume fabrication of sub-100 nm integrated circuits, The IPL system requires low axial energy spread ions in order to minimise the chromatic aberration of the projected image on the wafer. Ion energy spread for the multicusp source has been reduced from 6 eV to below 2 eV by the use of a planar magnetic filter. Most recently, LBNL successfully reduced the energy spread to below 1 eV by employing a co-axial filter configuration. A similar source is being fabricated to be used for a novel IPL machine to be built by LMS in 1999 as part of the European MEDEA project headed by Siemens. This paper describes the multicusp ion source for lithography and shows some exposure results using this source