Thermal frequency noise in dynamic scanning force microscopy
Thermal fluctuation of the cantilever position sets a fundamental limit for the precision of any scanning force microscope. In the present work we analyze how these fluctuations limit the determination of the resonance frequency of the tip-sample system. The basic principles of frequency detection i...
Gespeichert in:
Veröffentlicht in: | Journal of applied physics 2011-01, Vol.109 (2), p.024310-024310-10 |
---|---|
Hauptverfasser: | , , , , , , |
Format: | Artikel |
Sprache: | eng |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | Thermal fluctuation of the cantilever position sets a fundamental limit for the precision of any scanning force microscope. In the present work we analyze how these fluctuations limit the determination of the resonance frequency of the tip-sample system. The basic principles of frequency detection in dynamic scanning force microscopy are revised and the precise response of a typical frequency detection unit to thermal fluctuation of the cantilever is analyzed in detail. A general relation for thermal frequency noise is found as a function of measurement bandwidth and cantilever oscillation. For large oscillation amplitude and low bandwidth, this relation converges to the result known from the literature, while for low oscillation amplitude and large bandwidth, we find that the thermal frequency noise is equal to the width of the resonance curve and, therefore, stays finite, contrary to what is predicted by the relation known so far. The results presented in this work fundamentally determine the ultimate limits of dynamic scanning force microscopy. |
---|---|
ISSN: | 0021-8979 1089-7550 |
DOI: | 10.1063/1.3533769 |