| 摘要 |
Self-assembled nanowires are provided, comprising nanowires of a first crystalline composition formed on a substrate of a second crystalline composition. The two crystalline materials are characterized by an asymmetric lattice mismatch, in which in the interfacial plane between the two materials, the first material has a close lattice match (in any direction) with the second material and has a large lattice mismatch in all other major crystallographic directions with the second material. This allows the unrestricted growth of the epitaxial crystal in the first direction, but limits the width in the other. The nanowires are grown by first selecting the appropriate combination of materials that fulfill the foregoing criteria. The surface of the substrate on which the nanowires are to be formed must be cleaned in order (1) to ensure that the surface has an atomically flat, regular atomic structure on terraces and regular steps and (2) to remove impurities. Finally, epitaxial deposition of the first crystalline material on the cleaned surface is performed, thereby forming the self-assembled nanowires. Thus, one-dimensional epitaxial crystals are obtained with widths and heights at the nanometer scale, and lengths at the micrometer scale, which are aligned along certain crystallographic directions with high crystal quality.
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