A System for Replacement and Reuse of Tips in Atomic Force Microscopy

The ability to replace and reuse only the tip of the probe in an atomic force microscope (AFM) enables employing a greater variety of probes, enhancing their functionalities, and simplifying their use for imaging, metrology, and manipulation. This paper presents the development and evaluation of a system that employs a liquid meniscus at the end of an AFM probe as a microgripper to pick up tips, hold them during use, and subsequently drop them off. The system also comprises a tip supply station and a tip holder that supply new tips and preserve used tips for potential future reuse. The designs of the tip supply station and the tip holder are discussed, and the stiffness of the liquid meniscus is analyzed. Subsequently, a prototype of the system is fabricated. It is demonstrated to pick up a new AFM tip and image a calibration grating without any artifacts. The image is shown to be identical to that obtained by a conventional AFM probe. Likewise, tip detachment and reuse are also experimentally demonstrated. The reused tip is shown to image a calibration grating without artifacts, thereby demonstrating that the detachment and pick-up process does not deteriorate the quality of the replaceable AFM tip.