| With the availability of the novel isolated nanosprings or nanorods grown by the oblique angle vapor deposition technique, we employ the tip of an atomic force microscope (AFM) as the indentation tool to make the measurement of the mechanical properties of a single nanorod or a single nanospring possible. The procedure of AFM indentation technique is briefly described, and various factors that would affect either the data acquisition or the data analysis have been learned from our experience and are reviewed in detail.; We determined spring constants, Young's modulus of nanosprings and slanted nanorods using classical mechanical equations. Surprisingly, this matches well with our experimental results provided that the geometrical parameters and loading conditions (such as on axis or off axis) are properly accounted for.; In addition, we also show that a nanoscale structure such as a Co-coated Si nanospring can be electromechanically actuated when a do current up to 20 mA passes through it using a conductive (AFM) tip. The finite element modeling is used to estimate the magnetic force and actuated displacements as well as the spring constant. The obtained spring constant is independently checked using a mechanical loading. The electromechanical behavior appears to be similar to that of equivalent macroscopic coils.; Furthermore, the vibration of the AFM cantilever at its resonant frequency is utilized to trigger the cyclic load on a single slanted Si nanorod. The maximum load vs. the number of cycles to failure was measured and has an exponential decay behavior.; All these results presented here in the thesis are essential to the development of the nanodevices, nanomechanical and nanoelectromechanical systems (NEMS) and demonstrate the usefulness and challenges of AFM indentation technique for the mechanical, electromechanical and fatigue characterization of the isolated nanostructures. Most important of all, these findings show that within the sizes used in our work, we can apply macroscopic mechanical equations to the nanostructures. (Abstract shortened by UMI.)... |
