Formation of Sic Films on Silicon Field Emitters

Abstract

Thin films of silicon carbide have been formed on silicon field emitters by chemical reaction with ethylene (C2H4) at temperatures of 850 to 950°C using ethylene gas pressures up to 5×10-3 Torr. By controlling the reaction time and temperature, we have made SiC coatings of from ∼20 A thickness to complete transformation of tips to SiC (1-2 μm). The electron diffraction pattern of the SiC layers show the expected 20% lattice mismatch with silicon and, for those emitters completely transformed, a polycrystalline 3C-SiC polytype was identified. The small radius of curvature was maintained for both the coated and completely transformed tips, although some defects and surface roughness was introduced during the treatments.

Field-emission properties of vertically aligned carbon-nanotube array dependent on gas exposures and growth conditions

“…So far, great efforts have been made to enhance the field-emission properties using the sur- face sensitivity of the field emission. [15][16][17] It is possible that the degradation we have seen earlier is a consequence of surface modifications due to gas adsorbates. Similarly, the current saturation can be viewed as an adsorbate effect.…”