Characterization of AFM tips using nanografting

We introduce a new method, nanografting, to characterize atomic force microscopy tips. Our technique includes three main steps. First, a self-assembled monolayer (SAM) of thiol is imaged using AFM with a low imaging force. Second, under a high load, a line of new thiols is fabricated within the matrix SAM in a single scan. Finally, the resulting line is imaged by the same AFM tip under a reduced force. From the topographic image of the line, one can extract information regarding the top portion of the AFM tip and the tip–surface contact area during fabrication. The advantages of this approach include its simplicity, high speed, and the ability to characterize the very top portion of the tip. In addition, tips with multiple asperities, which are difficult to investigate using other approaches, can be easily identified and characterized via nanografting.