Formation of atomically sharp silicon needles

Summary form only given. An effort was made to exploit a known oxidation inhibition of silicon at regions of high curvature in order to develop emitter tips significantly sharper than those obtained previously. While this idea has already been proposed and used, the present study is the first to examine oxidation of conical silicon tips in some detail at high resolution. The results of this study are the development of a method for preparing uniform silicon tips with tip radii less than 1.0 nm and the clear demonstration of oxidation inhibition at a region of high and complex curvature. TEM images of two tips are shown at different magnifications. Fringes of the Si {111} planes with 3.13-angstrom spacing are seen at the tip. Contrast disappears where the tip diameter becomes less than 1.0 nm due to the limited number of atoms left to perform electron scattering.