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Development of a magnetic levitation force microscope
Author(s) -
GauthierManuel B.,
Garnier L.
Publication year - 1999
Publication title -
surface and interface analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 90
eISSN - 1096-9918
pISSN - 0142-2421
DOI - 10.1002/(sici)1096-9918(199905/06)27:5/6<287::aid-sia502>3.0.co;2-x
Subject(s) - magnetic levitation , electrostatic force microscope , levitation , cantilever , magnetic field , microscope , magnetic force microscope , magnet , instability , displacement (psychology) , van der waals force , non contact atomic force microscopy , optics , mechanics , chemistry , physics , materials science , mechanical engineering , microscopy , magnetization , engineering , kelvin probe force microscope , psychotherapist , composite material , psychology , quantum mechanics , organic chemistry , molecule
Classical atomic force microscopes use a soft cantilever spring toconvert the interaction between a tip and a surface into adisplacement. This leads to indirect force measurement andinstability in the case of attractive forces. We have developed a newkind of force sensor to overcome these limitations. The principle isto place a tip glued on a small magnet in levitation in a magneticfield. A servo‐loop ensures the stability of the equilibriumin the vertical direction and allows the measurement of forces. It ismonitored by an optical sensor that measures continuously the actualposition of the tip with a sensitivity of 10 pm. With such a deviceit is possible to obtain the van der Waals attraction up to themolecular contact without jump. A digital signal processing boardstops the approach of the tip just before contact to prevent anydeterioration of the surface during the measurement. This allowsimages of soft and brittle surfaces, such as a microfiltrationmembrane. Copyright © 1999 John Wiley & Sons, Ltd.