An Automated AFM Tip-Replacement System for In Situ Tip-Replacement

The increase in applications of the atomic force microscope (AFM) in industrial metrology has contributed to its increased automation. However, automatic replacement of the AFM tip without constraining the instrument's capabilities is still an important challenge. Here, in this article, we propose a system for automated replacement of the AFM tip that is compatible with all imaging modalities and requires minimal modification of a conventional AFM. The proposed strategy employs a wax microsphere as an adhesive for attaching a tip to a tip-less AFM probe and to subsequently detach it. A laser-based heating system and a visual servo control system, which includes an in-house developed out-of-plane motion measurement strategy, are employed for fast and accurate tip-replacement. The system is fabricated, calibrated, and automated tip-replacement is demonstrated with a tip positioning accuracy better than 0.3 μm and an average tip-replacement time of 10 s. Automated replacement of a deteriorated tip has been demonstrated in two specific cases, one in the context of repeated imaging, and another in the context of nanoindentation.