Prevention of copper corrosion on post-FIB wet stained sample using UV charge-neutralization method

Abstract This paper presents the study of various charge neutralization methods to prevent copper corrosion on post-FIB wet stained sample. Conventional fast and economic wet staining on post-FIB copper processed sample can sometimes cause unwanted artifact such as copper corrosion due to build-up of charges on non-grounded, long copper interconnect structures during FIB milling. Some charge neutralization methods such as probe-pin grounding, conductive paint application and UV treatment were investigated on an ET structure. The recommended method, using UV treatment, is applied to the die area on a bulk Si wafer and on a SOI (Si-on-insulator) wafer to compare the effect of this method in preventing the copper corrosion effect.