Abstract
This investigation deals with the process of electron emission from composite micro emitters consisting of a tungsten or carbon fiber core that has been coated with two types of dielectric materials: 1- Clark Electromedical Instruments Epoxylite resin (CEI- resin), 2- Epidian 6 (based on Bisphenol A) (E6-resin). Various properties of these emitters were measured, including the current voltage (I-V) characteristics that are presented as Fowler-Nordheim (FN) plots, in addition to the corresponding electron emission images. Measurements were carried out under ultra-high vacuum (UHV) conditions with a base pressure of 10(-8) mbar. Field electron microscope (FEM) standardized with 10 mm tip (cathode) - screen (anode) distance was employed to characterize the electron emitters.