Towards Automated AFM-based Nanohandling of DNA, SAMs and CNTs
Besides its ability of high resolution imaging, the Atomic Force Microscope (AFM) has been recognized as a valuable instrument for manipulation at the nanoscale. The characterization and manipulation of Carbon Nanotubes (CNTs) and DNA or the prototypical surface structuring of sensitive elements for biosensors are main applications for AFM-based nanohandling. The relatively low throughput induced by the sequential character of the AFM is one of the major drawbacks that arise, if the AFM is used as a robot for nanomanipulation. To increase the throughput as well as to achieve more reliable and industrial feasible results, automation of the necessary procedures has been proven to be the essential key feature.
The poster gives a short overview of the usage of the AFM in AMiR as a robot for nanohandling in general, and shows the latest results on automated nanomanipulation at dry ambient conditions. The handling of multi-walled CNTs on highly ordered pyrolytic graphite (HOPG) is shown, as well as the manipulation of double stranded lambda-DNA immobilized on silicon substrate. Figure 1 depicts several CNTs which were pushed, pulled, and cut by the AFM cantilever tip for building the shape of the acronym "CNT". These successful manipulations of nanoobjects in dry conditions are the first steps towards the implementation of an automated nanohandling in the future.
The development of an automated AFM-based nanostructuring technique for the design of high density sensitive elements (HDSE), using AFM lithography, is presented in the poster. Among other objectives, the accuracy of biosensors using AFM built HDSEs shall be increased compared to the usage of current technologies. As an example, figure 2 shows several 1 x 1 µm² sized elements in a (3-aminopropyl)-triethoxysilane (APTES) self-assembled monolayer. The results show the usage of this method for a high variety of structure widths covering the range between several nm up to several µm.
This poster was presented on NanoBioView, 6-7 October 2010
Division Microrobotics and Control Engineering (AMiR),
Carl von Ossietzky Universität Oldenburg, 26125 Oldenburg, Germany