Enhanced field emission from carbide-coated field emitters, and device applications

There is great interest in vacuum microelectronic devices using large compa ct field emitter arrays (FEAs), particularly flat panel displays and microw ave devices. FEAs made of Mo or Si have been used in most cases. However, b oth materials have characteristics which limit FEA performance in devices. At LRI we have studied other FEA materials which may enable superior perfor mance, particularly refractory carbides of transition metals such as ZrC. O ur experiments demonstrate and quantify significant advantages, particularl y reduced work function, more stable emission, greater tolerance of a degra ded environment, high emitted current capability, and resistance to ion bom bardment. With appropriate treatment and processing, it is possible to larg ely retain the advantages of carbides, either bulk emitters or thin coating s on Mo substrates, after exposure to air. (C) 1999 Elsevier Science B.V. A ll rights reserved.