Low-loss scanning electron microscopy can be used to investigate the
surface topography of solid specimens and provides enhanced image contrast
over secondary electron images. A high resolution-condenser objective lens
has allowed the low-loss technique to resolve separations of Au nucleii of
50Å and smaller dimensions of 25Å in samples coated with a fine grained
carbon-Au-palladium layer. An estimate of the surface topography of fine
grained vapor deposited materials (20 - 100Å) and the surface topography of
underlying single crystal Si in the 1000 - 2000Å range has also been
investigated. Surface imaging has also been performed on single crystals
using diffracted electrons scattered through 10−2 rad
in a conventional TEM. However, severe tilting of the specimen is required
which degrades the resolution 15 to 100 fold due to image
forshortening.