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The electric field in a silicon p–n junction has been measured using pixelated scanning transmission electron microscopy. By using a convergence angle of 3.2 mrad, a spatial resolution better than 1 nm can be achieved leading to a rigid shift of the transmitted beam as it passes through an electric field. By precessing the beam around the optical axis at an angle of 0.1°, the effects of dynamical diffraction can be reduced. This leads to an improved measurement of the electric field from the shift of the transmitted beam. Different algorithms have been used to measure this shift, and template matching leads to a more accurate measurement of the electric field than the often-used center of mass method. [ABSTRACT FROM AUTHOR]

• First application of phase shifting holography with Angstrom spatial resolution. • Specimen drift correction scheme for Fresnel affected atomic resolution holograms. • Software package provision for automatic data collection, drift correction and reconstruction. • Atomic scale electric field characterization and long-range fields at interfaces. • Discussion of spatial resolution, phase sensitivity and incomplete drift correction. Phase-shifting electron holography is an excellent method to reveal electron wave phase information with very high phase sensitivity over a large range of spatial frequencies. It circumvents the limiting trade-off between fringe spacing and visibility of standard off-axis holography. Previous implementations have been limited by the independent drift of biprism and sample. We demonstrate here an advanced drift correction scheme for the hologram series that exploits the presence of an interface of the TEM specimen to the vacuum area in the hologram. It allows to obtain reliable phase information up to 2π/452 at the 1 Å information limit of the Titan 80–300 kV environmental transmission electron microscope used, by applying a moderate voltage of 250 V to a single biprism for a fringe spacing of 1 Å. The obtained phase and amplitude information is validated at a thin Pt sample by use of multislice image simulation with the frozen lattice approximation and shows excellent agreement. The presented method is applicable in any TEM equipped with at least one electron biprism and thus enables achieving high resolution off-axis holography in various instruments including those for in-situ applications. A software implementation for the acquisition, calibration and reconstruction is provided. [Display omitted] [ABSTRACT FROM AUTHOR]