Off-axis electron holography of Si semiconductors prepared using FIB milling

Abstract

Off-axis electron holography is a powerful technique that can be used to provide 2D dopant maps of semiconductor materials. Focused ion beam milling is the only technique that can be used to prepare the parallel-sided specimens with the required site specificity for dopant profiling of state-of-the-art semiconductor devices. However, focused ion beam milling introduces artefacts into the thin TEM specimens, such as a surface amorphous layer, Ga implantation and the creation of defects. Here the effects of these artefacts in the semiconductor specimens are examined leading to a better understanding of the reconstructed phase images.