Focused ion beam specimen preparation for off-axis electron holography using Si, Ga, and Au ions

Silicon specimens containing p-n junctions have been prepared by focused ion beam milling using gallium, silicon, and gold ion sources. The specimens have been examined using off-axis electron holography and the total thickness of the electrically ‘inactive’ layer has been measured as 80, 140, and 410±15nm for the Au, Ga, and Si ions, respectively. We also show that the thickness of this damaged layer can be predicted using simulations.