Three-dimensional electrostatic potential of a Si p-n junction revealed using tomographic electron holography

Abstract

Off-axis electron holography and tomography have been combined to examine the 3-D electrostatic potential associated with a thin specimen containing a Si p-n junction. The device was prepared in a novel specimen geometry using focused ion beam milling, and a series of holograms was acquired over a tilt range of -70° to 70°. Simultaneous iterative reconstruction was used to reconstruct the 3-D electrostatic potential in the specimen. The experimental results were compared with simulations of the potential variation. Quantitative results from the central, 'bulk' semiconducting regions and from the surface layers were extracted from the 3-D reconstruction. © 2006 IOP Publishing Ltd.