There exist several methods reported so far for the fabrication of CNT tips. Each method has its own strengths and drawbacks. The simplest method is to attach a CNT directly to the base AFM tip manually using an acrylic adhesive while observing with an optical microscope.17 The method presents difficulties for accurate manipulation because an individual nanotube is not discernable with an optical microscope. A more sophisticated and expensive method is manufacturing in a vacuum chamber while viewing the individual nanotubes via a real time SEM image.32 Nanomanipulators installed in the SEM enable the manipulation with nanometer-level resolution. In contrast to the manipulation technique, some laboratories grow CNTs directly on AFM tips through chemical vapor deposition (CVD).19 With the CVD method, one can fabricate CNT tips on a wafer scale but some key issues not yet resolved include reproducible control of the length and growth direction of CNT. The FIB modification process described earlier can be applied to all CNT tips no matter how they are made, attached or directly grown, as long as they are not too poorly oriented.