Electron microscope image profiles of planar defects in crystals

Abstract

Bright- and dark-field electron microscope image profiles of inclined planar defects in crystals have been calculated, using the two-beam approximation, under a variety of diffraction and absorption conditions. It is found that the form of the fringe profiles depends in a complicated manner on the values of α—the fault phase angle, ω—the deviation from Bragg reflecting position, andξ_g/ξ_g—the ratio of the extinction distance to the anomalous absorption length. Many of the effects discussed have been observed in electron micrographs of stacking faults in thin foils of silicon.