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Acquisition of high precision images for non-contact atomic force microscopy via direct identification of sample height

Pishkenari, H. N ; Sharif University of Technology | 2005

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  1. Type of Document: Article
  2. DOI: 10.1115/IMECE2005-81627
  3. Publisher: 2005
  4. Abstract:
  5. Atomic force microscopes (AFM) can image and manipulate sample properties at the atomic scale. The non-contact mode of AFM offers unique advantages over other contemporary scanning probe techniques, especially when utilized for reliable measurements of soft samples (e.g., biological species). The distance between cantilever tip and sample surface is a time varying parameter even for a fixed sample height, and hence, difficult to identify. A remedy to this problem is to directly identify the sample height in order to generate high precision, atomic-resolution images. For this, the microcantilever is modeled by a single mode approximation and the interaction between the sample and cantilever is derived from a van der Waals potential. Since in most practical applications only the microcantilever deflection is accessible, this measurement is utilized to identify the sample height in each point. Using the proposed approach for identification of the sample height, the scanning speed can be increased significantly. Furthermore, for taking atomic-scale images of atomically flat samples, there is no need to use the feedback loop to achieve setpoint amplitude. Simulation results are provided to demonstrate the effectiveness of the approach and suggest the most suitable technique for the sample height identification. Copyright © 2005 by ASME
  6. Keywords:
  7. Atomic scale ; Atomic-resolution images ; Setpoint amplitude ; Van der Waals potential ; Approximation theory ; Atomic force microscopy ; Computer simulation ; Feedback control ; Mathematical models ; Van der Waals forces ; Imaging techniques
  8. Source: 2005 ASME International Mechanical Engineering Congress and Exposition, IMECE 2005, Orlando, FL, 5 November 2005 through 11 November 2005 ; Volume 74 DSC, Issue 2 PART B , 2005 , Pages 1335-1342 ; 0791842169 (ISBN); 9780791842164 (ISBN)
  9. URL: https://www.sciencedirect.com/science/article/abs/pii/S095741580600064X