Site-specific growth of Zno nanorods using catalysis-driven molecular-beam epitaxy

We report on catalyst-driven molecular beam epitaxy of ZnO nanorods. The process is site specific, as single crystal ZnO nanorod growth is realized via nucleation on Ag films or islands that are deposited on a SiO ₂-terminated Si substrate surface. Growth occurs at substrate temperatures on the order of 300-500°C. The nanorods are uniform cylinders, exhibiting diameters of 15-40 nm and lengths in excess of 1 μm. With this approach, nanorod placement can be predefined via location of metal catalyst islands or particles. This, coupled with the relatively low growth temperatures needed, suggests that ZnO nanorods could be integrated on device platforms for numerous applications, including chemical sensors and nanoelectronics.