This is a colorized micrograph of semiconductor nanowires grown at NIST in a precisely controlled array of sizes and locations. Credit: K. Bertness, NIST

NIST researchers grow nanowires made of semiconductors -- gallium nitride alloys -- by depositing atoms layer-by-layer on a silicon crystal under high vacuum. NIST has the unusual capability to produce these nanowires without using metal catalysts, thereby enhancing luminescence and reducing defects. NIST nanowires also have excellent mechanical quality factors.