Comprehensive Analysis of E478 Single-Component Epoxy Resin and Tungsten-E478 Interface for Metallic-Polymer Composite Electron Source Applications

This study provides comprehensive elemental, optical, and energy gap characteristics of the E478 single-component epoxy resin. This type of epoxy resin has imperative applications in medium voltage insulation and cold field emission of electrons. X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and hydrogen nuclear magnetic resonance (1H-NMR) were used to study the elemental and structural analyses, ultraviolet photoelectron spectroscopy (UPS) was used to obtain the local work function and the ionization potential energies, and ultraviolet/visible light spectroscopy (UV/VIS) was used to report the optical and energy gap characteristics of the epoxy resin being studied. Moreover, the UPS and UV/VIS analyses were merged to obtain the electron affinity of the E478 epoxy resin and to study the epoxy's energy band diagram and the tungsten-epoxy interface band structure. The results showed that the E478 epoxy resin is considered an n-type semiconductor of energy gap ∼3.94 eV, local work function ∼3.42 eV, ionization potential ∼6.10 eV, electron affinity ∼2.16 eV, and tungsten-epoxy Schottky contact barrier height ∼2.50 eV.