| As a useful tool for both imaging and modifying nanoscale structures, atomic force microscopes (AFM) have drawn many researchers' attention, but there are still many challenges such as lack of visual feedback during manipulation. In this dissertation, an AFM based nano manipulation system has been developed to modify the nanoscale structures including manipulation of nano particles, carbon nanotubes (CNTs) and indentation of the polymer substrate. These operations have been further assisted by real-time feedback such that AFM can be used to image, sense and manipulate nanoscale objects simultaneously. To address critical issues in AFM based nano manipulation, several methods have been developed to enhance the process of manipulation. In nano particle manipulation, a method called sequential parallel pushing (SPP) is presented for efficient and automated nano particle manipulation. Instead of using tip scanning to fully locate the particle center, this method uses contact loss detection to get the longitudinal position of particle and one scan line perpendicular to the pushing direction to determine the lateral position of the particle center. In nano indentation, computer-aided design (CAD) geometry processing has been integrated with an AFM based nano indentation process which enables the fabrication of complex geometric features. Machining parameters have been investigated and procedure to determine them have been demonstrated. In the localization of deformable nanoscale objects, two localization methods for localizing CNTs and nanowires have been introduced. They can perform accurate positioning and reconstruction of sample shapes while being manipulated. Successive manipulation strategies thus can be developed based on the developed fast localization schemes. |
