INTENSITY MEASUREMENT OF EQUAL-THICKNESS FRINGES IN TEM IMAGES OF WEDGE-SHAPED GAAS AND INP CRYSTALS BY A SLOW-SCAN CCD CAMERA

Exact measurement of profile intensity of thickness fringes has been c arried out in TEM images of a GaAs crystal and an InP crystal, by usin g a slow-scan CCD camera. The crystals have 90 degrees wedge-shape wit h the (110) and ((1) over bar 10) surfaces, and are axially illuminate d by a 175-keV electron beam along the [100] axes. The intensities, me asured in bright field and 002, 022, and 004 dark field images, are sh own as reliable experimental data on the electron diffraction. A multi -slice simulation program is checked by comparing the calculated diffr action intensities with the experimental data.