The changes of the work function (Phi) and the secondary electron emission (SEE) of oxygen covered polycrystalline tungsten occurring after ion sputtering and heat treatments have been investigated. The chemical composition was analyzed by X-ray photoelectron spectroscopy (XPS), and the electron emission properties by work function spectroscopy (WFS). We observed in what manner the chemical changes of the surface are reflected in the work function and SEE. The simultaneous change of Phi and SEE in the case of oxygen covered tungsten have been pointed out and a direct relationship between them can be supposed.

A simple method, compatible with conventional silicon technology, is introduced to generate SiC nanocrystals, embedded in SiO2 on Si, and aligned parallel with the interface. The nanometer-sized SiC grains were grown into SiO2 close to the Si∕SiO2 interface by a two-step annealing of oxide covered Si: first in a CO, then in a pure O2 atmosphere. The first (carbonization) step creates epitaxial SiC crystallites grown into the Si surface, while the second (oxidation) step moves the interface beyond them. Conventional and high-resolution cross-sectional electron microscopy shows pyramidal Si protrusions at the Si∕SiO2 interface under the grains. The size of the grains, as well as their distance from the Si∕SiO2 interface (peak of pyramids) can be controlled by the annealing process parameters.

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