Dynamical properties of the Q-controlled atomic force microscope

Kokavecz, János; Horváth, Zoltán L.; Mechler, Ádám
October 2004
Applied Physics Letters;10/11/2004, Vol. 85 Issue 15, p3232
Academic Journal
In intermittent contact mode atomic force microscopy (AFM), the quality factor (Q) of the oscillating probe is believed to account for the imaging speed and sensitivity. Q control is a method to artificially modify the quality factor of the probe. Here, we present a comprehensive study of the dynamics of the Q-controlled AFM. By comparing the analytical solutions of the force equations, we prove that the Q-controlled and non-Q-controlled systems are equivalent in the absence of surface forces. We also determine the conditions for the numerical simulation. In order to study the mechanism of contrast enhancement, we simulate the normal AFM operation including the surface forces. We found that there is a maximal probe sensitivity which cannot be exceeded even with Q control. Consistently, Q control enhances sensitivity only when imaging soft samples. Finally, we show that the phase signal of the Q-controlled system is more sensitive to the changes of the sample properties than in case of non-Q-controlled AFMs.


Related Articles

  • Small amplitude oscillations of a thin beam immersed in a viscous fluid near a solid surface. Green, Christopher P.; Sader, John E. // Physics of Fluids;Jul2005, Vol. 17 Issue 7, p073102 

    The hydrodynamic loading on a solid body moving in a viscous fluid can be strongly affected by its proximity to a surface. In this article, we calculate the hydrodynamic load on an infinitely long rigid beam of zero thickness that is undergoing small amplitude oscillations. The presence of a...

  • Insights into fluid tapping-mode atomic force microscopy provided by numerical simulations. Legleiter, Justin; Kowalewski, Tomasz // Applied Physics Letters;10/17/2005, Vol. 87 Issue 16, p163120 

    In an attempt to understand the physics underlying tapping mode atomic force microscopy (TMAFM) operated in fluids, simulations of complete TMAFM experiments were performed based on a cantilever model invoking the damped driven harmonic oscillator with a single degree of freedom with parameters...

  • Direct tip-sample interaction force control for the dynamic mode atomic force microscopy. Younkoo Jeong; Jayanth, G. R.; Jhiang, Sissy M.; Chia-Hsiang Menq // Applied Physics Letters;5/15/2006, Vol. 88 Issue 20, p204102 

    A control method, in which the tip-sample interaction force of each tapping cycle is directly regulated, is proposed for dynamic mode atomic force microscopy. It does not rely on the steady-state relationship between the cantilever’s oscillation amplitude and tip-to-sample distance, and...

  • Nonlinear dynamics of tapping-mode atomic force microscopy in liquid. Korayem, M. H.; Ebrahimi, N. // Journal of Applied Physics;Apr2011, Vol. 109 Issue 8, p084301 

    One problem in imaging is due to coexistence of double stable responses which can reduce the precision of the images. Our target is comparing coexistence of double responses in liquid with responses obtained in air. Contact forces have some differences in liquid in comparison to air in magnitude...

  • Modified atomic force microscopy cantilever design to facilitate access of higher modes of oscillation. Sadewasser, S.; Villanueva, G.; Plaza, J. A. // Review of Scientific Instruments;Jul2006, Vol. 77 Issue 7, p073703 

    The detection of higher modes of oscillation in atomic force microscopy can provide additional information on sample properties. However, the limited bandwidth of the photodiode in the beam deflection detection technique often limits the detectable frequency range. We present a novel cantilever...

  • Accurate formula for conversion of tunneling current in dynamic atomic force spectroscopy. Sader, John E.; Sugimoto, Yoshiaki // Applied Physics Letters;7/26/2010, Vol. 97 Issue 4, p043502 

    Recent developments in frequency modulation atomic force microscopy enable simultaneous measurement of frequency shift and time-averaged tunneling current. Determination of the interaction force is facilitated using an analytical formula, valid for arbitrary oscillation amplitudes [Sader and...

  • Observation of Antiphase Domains in CdxHg1 — xTe Films on Silicon by the Phase Contrast Method in Atomic Force Microscopy. Sabinina, I. V.; Gutakovskiǐ, A. K.; Sidorov, Yu. G.; Yakushev, M. V.; Varavin, V. S.; Latyshev, A. V. // JETP Letters;9/10/2005, Vol. 82 Issue 5, p292 

    It has been shown that phase contrast in atomic force microscopy (AFM) can be used to obtain adequate information on the density and distribution of antiphase domains on the surface of CdHgTe films grown by molecular beam epitaxy on a Si(301) substrate. By comparing the AFM phase images of the...

  • Thermally actuated tapping mode atomic force microscopy with polymer microcantilevers. Mitra, Bhaskar; Gaitas, Angelo // Review of Scientific Instruments;Feb2009, Vol. 80 Issue 2, pN.PAG 

    This paper demonstrates a thermally actuated tapping mode atomic force microscopy (AFM) with a polymer cantilever. The cantilever (350×250×3 μm3) is made from polyimide and includes an embedded resistive heater for thermal actuation. The oscillation of the cantilever is due to the...

  • Magnetostriction-driven cantilevers for dynamic atomic force microscopy. Penedo, M.; Fernández-Martínez, I.; Costa-Krämer, J. L.; Luna, M.; Briones, F. // Applied Physics Letters;10/5/2009, Vol. 95 Issue 14, p143505 

    An actuation mode is presented to drive the mechanical oscillation of cantilevers for dynamic atomic force microscopy. The method is based on direct mechanical excitation of the cantilevers coated with amorphous Fe–B–N thin films, by means of the film magnetostriction, i.e., the...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics