A novel low energy ion gun for ultra-shallow dopant depth profiling

Abstract

Ultra-shallow dopant depth profiling has been attracting more and more attention. This technique requires, first of all, a specific low energy ion gun which allows sputter-etching to be performed with sub-nm depth resolution. Since the depth-resolution of the sputter-etching profiling is substantially limited by atomic mixing caused by ion bombardment, the use of ion beam of low energies (< 500eV) with high current density is essential for the ultra-shallow dopant depth profiling. For this, several studies of low energy ion gun system have been intensively performed and achieved high depth resolution with considerable success. In the present study, we aimed at further improvement of the specific floating type ion guns, (FLIG), for wider applicability e.g. being attached to conventional surface analytical instruments through an ICF 70 Conflat flange. Performance of the newly developed FLIG was evaluated by attaching it to a scanning Auger electron microprobe, JAMP-10.