DARKFIELD AND BRIGHTFIELD TECHNIQUES FOR ELECTRON-MICROSCOPIC OBSERVATION OF ATOMIC STEPS ON MGO SINGLE-CRYSTAL SURFACES

Darkfield and brightfield techniques are presented for the observation of atomic steps on single-crystal surfaces of MgO. The exposure times for photographic recording of the darkfield and the brightfield micrographs were 2 min and 5 sec, respectively, at an electron-optical magnification of 20,000 times. The thickness of the MgO crystals and the height of the steps of 2.1 Å were measured from convergent-beam electron diffraction patterns. © 1979 North-Holland Publishing Company.