Stereoscopic Nanoscale-Precision Growth of Free-Standing Silver Nanorods by Electron Beam Irradiation

Nanoscale manipulation of atoms is desirable in modern technologies. Atoms in a material are typically manipulated by mechanical contact or thermal and electric effects. The electron beam of a scanning electron microscope is usually used for two-dimensional patterning of a substrate with nanoscale precision. Here we report stereoscopic growth of nanoparticles and nanorods on silver surfaces with nanometric precision under exposure to the electron beam with precise control over their position, size, and orientation. Nanorod length (50–1000 nm) and diameter (30–100 nm) can be independently controlled by adjusting the electron beam characteristics of a scanning electron microscope. Silver nanorods with diameters as small as 30 nm with location accuracy limited only by the resolution of the scanning electron microscope have been fabricated with repeatable orientation and size. Cascaded nanorod structures can be grown directly on other nanorods. The results open up a number of exciting possibilities for three-...