NSF Award
9461730
This Small Business Innovation Research Phase I project will investigate the feasibility of application of stochastically distributed microstructures for high performance field emission electron sources. At the present, the state-of-the-art high-current cathodes employ microfabricated field emitters that feature submicron tips with a packing density of the order of 10 7 / cm 2 and are capable of delivering a peak current density on the order of 1000 A/cm 2. However, the arrays of miniaturized field emitters require rather complicated and expensive processes to produce, hampering proliferation of electron sources based on these structures. This proposal describes a novel technique that has the potential to break through the current maximum output current density while significantly reducing the fabrication cost. Inexpensive templates that are commercially available will be used to fabricate stochastically distributed microstructures in a simple electrochemical process. The technique permits significantly higher packing density of field emission sites and larger active field emission area per microstructure, compared with the conventional microtip array cathode. The simplicity of this technique makes it a very promising approach for the fabrication of commercially viable high performance and broad-area cathodes.
