Georgia Tech researchers have built a highly sensitive atomicforce-microscopy (AFM) device capable of imaging 100 times faster than conventional AFM equipment.
Firat (Force-sensing integrated readout and active tip) lets scientists scan integrated circuits for both mechanical and material defects, and even makes it possible to film fast biological interactions on the molecular scale, tasks not possible with AFM.
Conventional AFM devices scan surfaces with a thin, sharptipped cantilever. Laser light bounced off the cantilever tip measures tip deflection as it moves along the surface and interacts with the material being analyzed. Actuator inertia limits scanning speed. But Firat gets around this limitation by combining the actuator and probe in a structure smaller than the size of a pinhead.
The group connected the Firat probe to a standard AFM controller and produced clear scans of nanoscale features at line speeds to 60 Hz. The system simultaneously imaged the topography as well as elastic and adhesive properties of carbon nanotubes, said to be a first. In fact, Firat can gather information on a material's topography, adhesion, stiffness, elasticity, and viscosity, all in one pass. Funding for the research comes from the National Science Foundation and the National Institutes of Health.