CONTRAST SIMULATION OF HIGH-RESOLUTION ELECTRON HOLOGRAPHY ON SURFACE-STRUCTURES

The advantage of electron holography in the study of the atomic structure of crystal surfaces with high spatial resolution is revealed by using a computer simulation in the case of the 7 x 7 superstructure on a clean Si(111) surface. The surface structure can be reconstructed from the hologram which also reproduces the 1 x 1 primary bulk structure with the same coordinates. A new algorithm for image restoration is applied successfully to this reconstructed image. The effect of aberrations of a transmission electron microscope instrument is eliminated and the typical structure of the surface is represented.