Towards automatic nanomanipulation: drift compensation in scanning probe microscopes

Manipulation of nanoparticles with atomic force microscopes (AFM) has been under development for a decade, and is now well established as a technique for prototyping nanodevices and for other applications. The manipulation process tends to be labor-intensive because a user is needed in the loop to compensate for the numerous uncertainties associated with AFM operation. This work addresses thermal drift, which is the major cause of errors for AFM operated in ambient conditions. It is shown that drift can be estimated efficiently by using Kalman filtering techniques. Preliminary results indicate that drift compensation enables manipulation of groups of particles under program control, without human intervention, in ambient air and at room temperature. This is a first step towards fully automatic nanomanipulation, which would permit assembling, from the bottom up, nanostructures much more complex than those being built today with AFM.