SMART · Scanning Microscopy using Active Resonating nanoTips

This SMART application proposes a technological breakthrough in the field of Atomic Force Microscopy (AFM). It aims at introducing Micro/Nano Electromechanical Systems (MNEMS) as a new generation of AFM probes having outstanding performances in terms of sensitivity and acquisition rate. More precisely, we aim at using bulk mode microresonators to drive an oscillating nanotip in the GHz range. Many applications are expected in the emerging fields of nanobiosciences. AFM systems have been widely used for 20 years in academic and industrial work. They give access to microscopy images at the nanoscale and derived techniques allow many physical characterizations. Many labs are currently trying to use the oscillating mode of AFM to probe biological nanosystems and their dynamics in a liquid environment. However, AFM performances are limited by the AFM oscillator itself. It is typically made of a tip supported by a cantilever beam whose oscillating properties are drastically degraded once placed in a liquid. This phenomenon is due to the hydrodynamic drag and the added mass of the liquid. Consequently, the resonant frequencies and quality factors are too low in liquids to support the force sensitivity and acquisition rate required to probe biological nanosystems dynamics. The SMART project proposes to change the overall AFM oscillator and to choose an oscillation mode in the GHz range that reduces the liquid velocity gradient around the resonator. This new generation of high sensitivity AFM force sensor will be an unprecedented tool for imaging biological and chemical systems at the nanoscale and the possibility of kinetic spectroscopy in liquids. AFM performances are expected to be increased by 3 orders of magnitude. The SMART investigator has a 10 year background in AFM and a 7 year experience in MNEMS resonators. Today, there is no project strictly similar to this one at international level. If successful, Europe could become a leader in this high level competition.