Atomic scale imaging of surfaces in UHV

Abstract

Electron Microscopy of surfaces can in principle provide information that is not available by other techniques. Arguably the most significant is information about the surface structure simultaneously with the bulk atomic structure. Whereas bulk atomic scale information is now routinely available using standard high resolution imaging techniques, imaging surface with similar resolution has proved far harder. To date the only extensively used technique is profile imaging, but this has an inherent scientific problem; the imaged area is so thin that there is great uncertainty about how representative the results are of a bulk surface. For instance, one can conclude almost without ambiguity that any results on large unit cell surface structures will be erroneous since the long range elastic strains will be truncated by the specimen thickness.