Field emitting device comprising field-concentrating nanoconductor assembly and method for making the same

摘要

This invention is predicated on applicants' discovery that a highly oriented nanoconductor structure alone does not guarantee efficient field emission. To the contrary, the conventional densely populated, highly oriented structures actually yield relatively poor field emission characteristics. Applicants have determined that the individual nanoconductors in conventional assemblies are so closely spaced that they shield each other from effective field concentration at the ends, thus diminishing the driving force for efficient electron emission. In accordance with the invention, an improved field emitting nanoconductors assembly (a "low density nanoconductor assembly") comprises an array of nanoconductors which are highly aligned but spaced from each other an average distance of at least 10% of the average height of the nanoconductors and preferably 50% of the average height. In this way, the field strength at the ends will be at least 50% of the maximal field concentration possible. Several ways of making the optimally low density assemblies are described along with several devices employing the assemblies.