Date of Award
Master of Science
Electrical and Computer Engineering
We propose a fast method to reconstruct the curve of tip-surface force v.s. distance
in Atomic Force Microscopy (AFM). A precise and fast force curve reconstruction can
help improve research in material science, biological science, chemistry, etc. Existing
techniques require multiple sinusoids at the input to introduce intermodulation terms,
i.e., exponential components at equally spaced frequencies, and the estimation is done
by balancing those terms. Instead of using intermodulation terms, our method tries to
balance time domain samples. The method is based on the assumption that a discrete
model approximates the continuous AFM model well when sampled at high frequency.
Least Squares method is used to derive a polynomial approximating the force curve.
The new method can make use of samples in the transient process and does not require
multiple sinusoids at the input. It has potential benets in taking less testing time,
getting more accuracy and acquiring force curves of several materials in one experiment.
Wang, Wenyu, "Fast estimation of nonlinearities in atomic force microscopy" (2015). Graduate Theses and Dissertations. 14424.