Abstract: A method for automatically aligning a scanning tunneling electron microscope (STEM) for acquiring precession electron diffraction (PED) mapping data includes the generation of an incident electron beam aligned with a STEM optic axis and focused on a sample region. A non-inclined signal is acquired of the spatial distribution from the sample region, by scanning the aligned incident beam across multiple discrete locations and acquiring a signal associated with each location. The method can further include the inclination of the incident electron beam to a fixed inclination angle relative to the optic axis and then acquiring an inclined signal spatial distribution from the sample region by scanning the inclined incident beam across the multiple discrete locations while applying a cyclic azimuthal scanning protocol to the inclined beam and acquiring a signal associated with each location.

Abstract: The object of the present invention provides a scanning transmission electron microscope with the ability to formed at least one diffraction pattern. The scanning electron microscope comprises an electron source, which is configured to provide primary electron beam, a condenser lens system, an objective electromagnetic system, a projection lens system and a detection system, in addition, the objective electromagnetic lens consists of an upper pole piece and a lower pole piece, wherein each pole piece comprises a pole piece face, which is a flat surface oriented towards a sample plane. A salient feature of the present invention is to form at least one diffraction pattern located in the distance from the lower pole piece face outside the pole piece gap, wherein the pole piece gap is the space between the upper pole piece face and the lower pole piece face.

Abstract: The object of the present invention provides a scanning transmission electron microscope with the ability to formed at least one diffraction pattern. The scanning electron microscope comprises an electron source, which is configured to provide primary electron beam, a condenser lens system, an objective electromagnetic system, a projection lens system and a detection system, in addition, the objective electromagnetic lens consists of an upper pole piece and a lower pole piece, wherein each pole piece comprises a pole piece face, which is a flat surface oriented towards a sample plane. A salient feature of the present invention is to form at least one diffraction pattern located in the distance from the lower pole piece face outside the pole piece gap, wherein the pole piece gap is the space between the upper pole piece face and the lower pole piece face.

Abstract: A scanning transmission electron microscope is adapted to acquire high quality precession electron diffraction (PED) patterns by means of separated scanning deflectors and precession deflectors. Magnetic or electrostatic deflectors may be used for scanning and for precession. This enables independent optimization of parameters for each deflection system to achieve a broad operating range simultaneously for both deflection systems.