28.2: Formation of Nano‐structured Molybdenum Microtips by Reactive Ion Etching of Polyimide‐Coated Field Emitter Arrays

Morphologies of Spindt-type molybdenum microtips were modified by reactive ion etching following polyimide coating on field emitter arrays(FEAs). The modification produces nano-structured apexes on the microtips. The nano-structured geometry provides multiple emission sites to lower the driving gate bias by around 30V and to remarkably improve emission uniformity on 5.2″ FEAs. In addition, the double-gated FEAs, which are stable in a high voltage operation, were fabricated to achieve high brightness by taking advantage of the modification process.