Nucleation control for ZnO nanorods grown by catalyst-driven molecular beam epitaxy

Abstract We report a study of the annealing temperature and time on Ag catalyst size and density for subsequent growth of ZnO nanorods by catalyst-driven molecular beam epitaxy (MBE). Two different substrates (SiO 2 and SiN X ) for the Ag deposition were used and the thickness of the Ag held constant at 25 A. Annealing between 600 and 800 °C produced Ag cluster sizes in the range 8–30 nm diameter on SiO 2 and 10–65 nm on SiN X with a cluster density from 100 to 2500 mm −2 for SiO 2 and 30 to 1900 mm −2 for SiN X . ZnO nanorods grown on these clusters show single-crystal, wurtzite-phase nature and strong band-edge photoluminescence at 380 nm. The nanorods can also be grown selectively on lithographically-patterned dielectric stripes with Ag clusters formed on top by e-beam evaporation and annealing.