Ultralow threshold field emission from a single multipod structure of ZnO

The field emission of individual ZnO multipods and a single arm of a multipod structure grown by a vapor deposition were carried out. A current of 1 nA with an ultralow onset voltage of 40 V was observed repeatedly for the single multipod as well as for the arm. The nonlinearity observed in the Fowler-Nordheim plots have been interpreted on the basis of the theory of electron emission from semiconductors and a scheme explaining the field emission behavior in both the high- and low-field regions owing to the very high geometrical factor has been picturized. (c) 2006 American Institute of Physics.