The Study Of An Improved AFM For Large Scan Range

The Atomic Force Microscope (AFM) is a powerful instrument for the scientificresearch in the micro-nano scale. In China, a piezo tube is applied in common AFMproduct to scan specimens, thus the scan range is very limited. This limitationhampers the application of AFM in biological research. In order to solve this problem,this dissertation provides a method of the design and manufacture of an experimentalAFM instrument with a large scan range, based on the current AFM productNSPM6800.According to the fundamentals of the AFM, there are two aspects to increase thescan range. On one hand, the piezo scanner should be improved;on the other hand,the configuration of AFM head should be changed. Then, this dissertation collects thetypical configurations of current AFM instruments, as well as that of the NSPM 6800.After that, the steps of how to increasing the scan range of NSPM 6800 is presentedas follow : 1)using the piezostack in stead of the piezo tube scanner to increase scanrange;2)separating the XY and Z piezo scanner apart;and 3)designing a noveldeformation detecting system.The core part of this study is to design and manufacture a new AFM head. Thedifficulties of this work lie in having to consider a mass of factors, like the laser, thereflecting mirror, the AFM tip, the PSPD, the piezo scanner, the motion flat, and etc.Associated with the controller of the NSPM 6800, an experimental AFMinstrument was developed, and the calibration grating was scanned for theperformance. Specimen images large as 100μm×100μm were obtained successfully.This work was supported by the National Natural Science Foundation of China,granting Number 10427401.