Correction of distortion due to thermal drift in scanning probe microscopy.

A common source of distortion in scanning probe microscope (SPM) images is "thermal drift," the slow thermal expansion of different materials in the sample and microscope due to small changes in temperature over the course of a scan. We describe here a method for correcting this distortion by immediately following each image scan with a rescan of a small, narrow portion of the same area with the slow and fast scan axes reversed. The original, full image is corrected using a low-order polynomial mapping function, with coefficients determined by a pixel-wise comparison between the original full and rescanned partial images.