“Column-By-Column” Compositional Mapping At Semiconductor Interfaces Using Z-Contrast Stem

Abstract
A new strategy for atomic resolution compositional mapping at semiconductor interfaces is presented. Images can be interpreted directly to within 10% to give column-by-column compositional information with a sensitivity approaching Rutherford scattering cross sections. We apply the method to obtain the first atomic resolution images of interfacial ordering in ultrathin (SimGen)p superlattices and attribute the results to growth on (2 × 1) and (1 × 2) reconstructed surfaces.