FIELD-EMISSION PROPERTIES OF ULTRASMALL ZR SPOTS ON W

The aims of the investigation were to obtain small and supersmall Zr/ZrO spots on W surface, estimating the limit emission capabilities of such systems, and to analyze their physical mechanisms, which determine their stability. Ultrasmall Zr spots with radii of approx.100 angstrom were obtained. For such spots field emission current densities of approx.109 A/cm2 were achieved in stationary regime. The numerical simulation of the emitter heating in the three-dimensional axial-symmetrical model showed good qualitative agreement with the experimental results for both localized and nonlocalized emission.