image: This is a high-resolution transmission electron microscope image of a nanowire. The atomic structure of the wire is visible as the fine fringes in the image. The nanowire is 16nm in diameter and is made of Si capped with a thin (3nm; 10 atomic bilayers) Ge layer grown from a solid AuAl alloy catalyst. The interface between Si and Ge is relatively sharp -- measurements of the composition show that it changes over one or two atomic planes. This image relates to an article that appeared in the Nov. 27 issue of Science, published by AAAS. The study, by Dr. C.-Y. Wen at Purdue University in West Lafayette, Ind., and colleagues, was titled, "Formation of Compositionally Abrupt Axial Heterojunctions in Silicon-Germanium Nanowires." view more
Credit: Image courtesy of IBM