Compact stand‐alone atomic force microscope

A stand-alone atomic force microscope (AFM) featuring large scan, friction measurement, atomic resolution, and liquid operation, has been developed. Cantilever displacements are measured using the optical beam deflection method. The laser diode and focusing lens are positioned inside the piezo tube and the cantilever at the end of the piezo tube. Because the laser beam stays o­n the cantilever during scanning, the scan range is solely determined by the characteristics of the piezo tube. In our case 30 x 30 x 9.5 mum3 (xyz). The optical beam deflection detection method allows simultaneous measurement of height displacements and torsion (induced by lateral forces) of the cantilever. AFM images of dried lymphocytes reveal features in the torsion images, which are o­nly faintly visible in the normal height images. A new way of detecting the nonlinear behavior of the piezo tube is described. With this information the piezo scan is linearized. The nonlinearity in a 30-mum scan is reduced from 40% to about 1%, as is illustrated with images of a compact disk. The stand-alone AFM can be combined with a (confocal) inverted microscope, yielding a versatile setup for biological applications.

[1]  Othmar Marti,et al.  Combined scanning force and friction microscopy of mica , 1990 .

[2]  R. Barrett,et al.  Optical scan‐correction system applied to atomic force microscopy , 1991 .

[3]  D. Sarid,et al.  Compact scanning-force microscope using a laser diode. , 1988, Optics letters.

[4]  J. Frommer,et al.  Friction measurements on phase-separated thin films with a modified atomic force microscope , 1992, Nature.

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

[6]  C. J. Chen,et al.  Electromechanical deflections of piezoelectric tubes with quartered electrodes , 1992 .

[7]  P. Haydon,et al.  Actin filament dynamics in living glial cells imaged by atomic force microscopy. , 1992, Science.

[8]  J. Greve,et al.  Atomic force microscope with integrated optical microscope for biological applications , 1992 .

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

[10]  Othmar Marti,et al.  A stand-alone scanning force and friction microscope , 1992 .

[11]  N. Amer,et al.  Simultaneous measurement of lateral and normal forces with an optical‐beam‐deflection atomic force microscope , 1990 .

[12]  John D. Baldeschwieler,et al.  Lateral forces during atomic force microscopy of graphite in air , 1992 .

[13]  N. Amer,et al.  Erratum: Novel optical approach to atomic force microscopy [Appl. Phys. Lett. 53, 1045 (1988)] , 1988 .

[14]  J. Baldeschwieler,et al.  Scanned‐cantilever atomic force microscope , 1993 .

[15]  Jan Greve,et al.  New imaging mode in atomic-force microscopy based on the error signal , 1992, Photonics West - Lasers and Applications in Science and Engineering.

[16]  D. Sarid,et al.  Improved atomic force microscope using a laser diode interferometer , 1992 .