Large-area zinc oxide nanorod arrays templated by nanoimprint lithography: control of morphologies and optical properties.
Vertically aligned, highly ordered, large area arrays of nanostructures are important building blocks for multifunctional devices. Here, ZnO nanorod arrays are selectively synthesized on Si substrates by a solution method within patterns created by nanoimprint lithography. The growth modes of two dimensional nucleation-driven wedding cakes and screw dislocation-driven spirals are inferred to determine the top end morphologies of the nanorods. Sub-bandgap photoluminescence of the nanorods is greatly enhanced by the manipulation of the hydrogen donors via a post-growth thermal treatment. Lasing behavior is facilitated in the nanorods with faceted top ends formed from wedding cakes growth mode. This work demonstrates the control of morphologies of oxide nanostructures in a large scale and the optimization of the optical performance.
Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA. Singapore-MIT Alliance, National University of Singapore, 4 Engineering Drive 3, 117576 Singapore.
Chen
C
Zhang
Xiaohu
X
Huang
Hongfei
H
Liu
Soo Jin
SJ
Chua
Caroline A
CA
Ross