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Selected Applications nanotools UK Scientists Discover Strongest Biological Material Did you know that limpets’ teeth are the world’s strongest known biological material? The group of Prof. Asa Barber in the UK explored this using an attoAFM (inside a SEM): their observations highlight an absolute material tensile strength that is the highest recorded for a biological material [1]. This considerable tensile strength of limpet teeth is attributed to a high mineral volume fraction of reinforcing goethite nanofibers with diameters below a defect controlled critical size, suggesting that natural design in limpet teeth is optimized to- wards theoretical strength limits. For further reading see: www.bbc.com/news/science-environment-31500883 Image courtesy of Asa H. Barber, Dun Lu, Nicola M. Pugno. [1] Barber AH, Lu D, Pugno NM. J. R. Soc. Interface 12: 20141326 [2015]. http://dx.doi.org/10.1098/rsif.2014.1326 In-Situ Characterization of Exposed E-Beam Resist using a Novel AFM Technique In this application, attocube‘s ultra-compact attoAFM III is mounted directly below the cathode of an e-BL-system. The relative position of the sample with respect to the e-beam is controlled by piezo xy positioning units. The coarse distance of the AFM tip to the sample is further controlled by the piezo z positioner. This arrangement allows the user not only to irradiate the sample with the e-BL-system but also to independently image the irradiated resist with the AFM - without the need of breaking the vacuum and developing the resist. This unique capability allows scientists to adjust e-beam doses in a much more time efficient fashion than previous techniques and to pin-point and understand critical processes in nm-scale lithography processes. References: [1] H. Koop et al., J. Vac. Sci. Technol. B 28, 802 (2010). [2] Raith application note: „Enabling sub-nm 3D metrology inside an Electron Beam Lithography (EBL) tool by integration of an in-situ Atomic Force Microscope (2011). attoMICROSCOPY Sophisticated Tools for Science PAGE 191