Atomic force microscope with magnetic force modulation

We have constructed a scanned stylus atomic force microscope (AFM) with direct force modulation and integrated microfluorescence optics. The instrument was designed to image the surface of massive samples under various ambient conditions. In force modulation microscopy the imaging force is modulated during the scanning process via an external magnetic field that acts directly on the magnetic AFM tip. Polymeric Langmuir–Blodgett films on silicon oxide were imaged to evaluate the application range of the instrument. We demonstrate that direct force modulation microscopy permits the quantitative recording of the local complex compliance both as a function of the location and as a function of the frequency. In a novel imaging mode referred to as sample resonance mode, the contrast of the image can be selectively enhanced based on local elasticity differences.

[1]  K. Kendall,et al.  Surface energy and the contact of elastic solids , 1971, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[2]  Bell,et al.  Elastic properties of Langmuir-Blodgett films. , 1986, Physical review letters.

[3]  G. McClelland,et al.  Atomic scale friction between the muscovite mica cleavage plane and a tungsten tip , 1988 .

[4]  G. Sagulin,et al.  Effect of duct obstruction on structure, elemental composition, and function of rat submandibular glands. , 1989, Scanning microscopy.

[5]  H. Gaub,et al.  A miniaturized micro-fluorescence film balance for protein-containing lipid monolayers spread from a vesicle suspension. , 1991, Journal of biochemical and biophysical methods.

[6]  H. Hansma,et al.  Atomic force microscopy: seeing molecules of lipid and immunoglobulin. , 1991, Clinical chemistry.

[7]  P. Hansma,et al.  Using force modulation to image surface elasticities with the atomic force microscope , 1991 .

[8]  J. Frommer,et al.  Molecular-resolution images of Langmuir–Blodgett films using atomic force microscopy , 1991, Nature.

[9]  M. Radmacher,et al.  Molecular order in polymerizable Langmuir-Blodgett films probed by microfluorescence and scanning force microscopy , 1992 .

[10]  P. Hansma,et al.  Atomic-scale imaging of calcite growth and dissolution in real time , 1992 .

[11]  C. Siegerist,et al.  Reproducible Imaging and Dissection of Plasmid DNA Under Liquid with the Atomic Force Microscope , 1992, Science.

[12]  H. Hansma,et al.  Polymerized LB Films Imaged with a Combined Atomic Force Microscope-Fluorescence Microscope , 1992 .

[13]  M. Radmacher,et al.  An AFM with integrated micro-fluorescence optics: design and performance , 1992 .

[14]  M. Radmacher,et al.  Surface structure of hydrated amorphous silicon oxide at 3 Å resolution by scanning force microscopy , 1992 .

[15]  M. Radmacher,et al.  From molecules to cells: imaging soft samples with the atomic force microscope. , 1992, Science.

[16]  M. Radmacher,et al.  Imaging viscoelasticity by force modulation with the atomic force microscope. , 1993, Biophysical journal.

[17]  P. Hansma,et al.  A nondestructive method for determining the spring constant of cantilevers for scanning force microscopy , 1993 .

[18]  M. Radmacher,et al.  Monomeric and polymeric molecular films from the diethylene glycol diamine pentacosadiynoic amide , 1993 .