Analysis Of System And Image In Scanning Probe Microscope

In the research of nano-scale imaging, more attentions are paid to new technology and new instrument, while the rehandling to the images is ignored by most people.Scanning Probe Microscope is an important type of instrument to obtain the nano-scale images. But mere are some differences between the images and real sample surface. Among all the factors that lead to these differences, I chose two important factors as my directions for my master degree.One factor is the role of Electric Feedback System in imaging, for the status of instrument decides the quality of images directly. After studying each part of the instrument, I write a compute code to simulate the process when tip move along the surface. This method can not only show the operation of each part clearly, but also be applied to experiment to choose the parameters while this work is done empirically heretofore. Many conclusions can be drawn: the amplitude increases with the descending of integral gain and the increasing of proportional gain; the move of tip is dominated by the combination of integral and proportional circuit; the effect of proportional gain to amplitude of tip is more intense than that of integral gain; a critical valve is existed in the course of modulating the integral gain. The former two conclusions coincide with the experiences and the later two are discovered with the help of this method. Furthermore, this method gives a bright future for improving instrument and removing the effect of apparatus from images.The work of removing the effect to image from probe is study and the shortcoming is point out which limits wide application. Basing on the relationship of probe and surface, I propose a novel method. In this method, according to the character of the tip, the lateral of probe can be build from the local areas in image. Therefore the image can be reconstructed. An AFM image is used to verify this method. The lateral coincides with the SEM image of tip, and the reconstructed image is ideal. In addition, many advantages ensure the method can be applied widely.