Single crystal diamond probes for atomic-force microscopy

Results obtained in the development and testing of high-strength, chemically inert, and sharply pointed single crystal diamond probes for atomic-force microscopy are presented. The probes were fabricated on the basis of pyramidal diamond single crystals produced by selective oxidation of polycrystalline films grown by chemical vapor deposition. A procedure was developed for attachment of single needles to cantilevers of silicon probes. A transmission electron microscope was used to find that the apical angle of the pyramidal diamond crystallites is about 10$^\circ$ and the radius of curvature of the apex of the diamond crystallite is 2–10 nm. It is shown for the example of two test samples (graphite surface and DNA molecules) that the diamond probes can be effectively used in atomic-force microscopy and make it possible to improve the image quality compared with standard silicon probes.