Nanoscale In-plane Deformation Studies Using Atomic Force Microscopy And Digital Image Correlation Techniques

Recent development of nanofabricating has brought the requirement of analyzing tools which could precisely characterize the mechanical properties of microstructures, whose deformation displacement is smaller than a few microns. Till present day, the methods and technology used to investigate the deformation behavior in nanoscale are still lacking. Traditional analyzing tools cannot achieve the sampling resolution and sensitivity on microscale or nanoscale. By using atomic force microscope (AFM) integrated with an in- situ tensile system, topography images are obtained and then these images are analyzed by digital image correlation (DIC) processing approach as well as quantitative deformation measurement is obtained. The contents of this thesis are described as follows.First of all, to determine if DIC technique can be used for deformation analyzing, some AFM images whose deformation is known are used for DIC analyzing. Images of before and after deformation of a in-situ stretched specimen are get from CCD camera. After processing these images by using DIC software, the mechanical properties of the specimen are presented.Besides, AFM has image distortions due to non-linearity, hysteresis of the piezo scanner during the imaging process. The distortion has strong negative effects on DIC processing. By implementing calibration procedures, errors are eliminated. Compare scanning component with each other and find out the best components for DIC analyzing.Finally, a tape band and copper ware are stretched with in-situ tensile stage and the topography images are got by AFM. After that, the images are analyzed by DIC technique. After numerical analyzing, the result shows that DIC method is fit for sudden change of specimen surface, such as peeling off of oxide layer. For magnetic band, the creep deformation while stretching is discussed. The deformation behavior of the tape is also presented.