Chemical vapor deposition diamond for tips in nanoprobe experiments

Diamond is the most suitable material for many experimental methods in nanoprobe microscopy and materials testing. The extreme hardness, the high Young’s modulus, the inert nature of the surface, and the electrical conductivity obtained through doping make this material particularly attractive. We have coated silicon atomic force microscope (AFM) levers with thin (100 nm) doped diamond layers by chemical vapor deposition (CVD). A continuous diamond coating was obtained, resulting in tips with 100–200 nm radii. Owing to their electrical conductivity, these tips were found to be adequate for conducting AFM and scanning tunneling microscope applications, some of which are briefly discussed and reviewed in this article. We have also demonstrated CVD diamond tips, microfabricated in a controlled fashion, that have a 20 nm apex radius. These tips are particularly promising for nanomechanics and general AFM use.