Forward and retraced scanning combined imaging method for fast scanning atomic force microscopy

For nearly all atomic force microscopies (AFMs) utilized now, only the signals in forward scanning process are employed to reconstruct the sample surface topography, while the retraced scanning process is just for adjustment. In this paper, a forward and retraced scanning combined imaging method for AFM is proposed to increase surface reconstruction accuracy. Specifically, two reconstructed topography images are obtained, one is for forward scanning and the other is for retraced scanning; the hysteresis distortion is compensated with a data fusion based post-processing method; then the two images are combined together with confidence levels to reconstruct the final accurate topography image. This novel imaging method is especially valid for fast scanning tasks, when it is hard to accurately reconstruct the sample surface topography with only forward scanning signals. Some simulation and experimental results are included to demonstrate the superior performance of the proposed imaging method.