This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The research objective of this award is to develop fundamental understanding of the effect of probe-sample thin-fluid-film forces on the accuracy of dynamic atomic force microscopy (AFM) images acquired in ambient air. In particular, the work will quantify the impact of environmental, imaging parameter and chemical composition variables on the emergence of imaging artifacts, such as multistability, whereby up to an infinite number of images can be obtained for the same sample, probe and set of imaging parameters in tapping-mode AFM. The project relies on imaging and spectroscopy AFM experiments to be conducted under controlled environmental conditions with standard and customized probes, scanning tunneling microscopy and transmission electron microscopy experiments, and atomistic, continuum and nonlinear dynamics AFM simulations. Deliverables include a catalog of quantitative relationships between the parameters governing thin-fluid-film probe-sample forces and the accuracy of the acquired topographical images, multi-scale modeling and analysis tools, demonstration and validation via hardware, documentation of research results and engineering student education.
If successful, the results of this research will aid in the correct interpretation of AFM experiments performed on a variety of nanostructures commonly used in high-impact technologies such as MEMS/NEMS, biotechnology, microrobotic surgery, drug design, tissue engineering, etc., where accurate topographical measurements are critical and could impact the well-being of human beings. Additionally, the application of theoretical and experimental nanoscale science to specific research problems will contribute to the education of the next-generation workforce. This will take place in the short term through enrichment of an existing multi-scale simulation course, through research internships for high-school seniors participating in the University of Maryland (UMD) Pre-College Program and through short research projects for undergraduate students enrolled in the UMD Inventis Academy of Leadership.
