Challenges and complexities of multifrequency atomic force microscopy in liquid environments

• Santiago D. Solares

Beilstein J. Nanotechnol. 2014, 5, 298–307, doi:10.3762/bjnano.5.33

• techniques. Finally, it is noted that some of the challenges discussed here, namely those caused by sharp variations in the tip–sample forces can be mitigated through the use of small-amplitude operation [7][8], although this may not always be feasible, depending on the type of sample and the type of

Frequency, amplitude, and phase measurements in contact resonance atomic force microscopies

• Gheorghe Stan and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2014, 5, 278–288, doi:10.3762/bjnano.5.30

• sensitivity. However, with the exception of small-amplitude FM-AFM [28][29] in which the tip–sample force gradient can be measured directly, the mapping of Vts and Pts in intermittent-contact imaging generally only provides a qualitative map of surface viscoelasticity. In this work the focus is on the CR-AFM

Friction behavior of a microstructured polymer surface inspired by snake skin

• Martina J. Baum,
• Lars Heepe and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2014, 5, 83–97, doi:10.3762/bjnano.5.8

• , (2) additional application of dampening polymers, (3) use of specific microstructures or (4) application of vibrations (e.g., [23][29]). The application of small amplitude vibrations perpendicular to the sliding direction is a remarkable approach to eliminate stick-slip. This mechanical control of

Noise performance of frequency modulation Kelvin force microscopy

• Heinrich Diesinger,
• Dominique Deresmes and
• Thierry Mélin

Beilstein J. Nanotechnol. 2014, 5, 1–18, doi:10.3762/bjnano.5.1

• surface, as illustrated in Figure 16, is described by a power law derived from the second derivative of the capacitance [21]. Here we make the approximation that the probe oscillates with a small amplitude D0 around a larger average probe distance z. Hence For thermal noise domination, Equation 38, the

Bimodal atomic force microscopy driving the higher eigenmode in frequency-modulation mode: Implementation, advantages, disadvantages and comparison to the open-loop case

• Daniel Ebeling and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2013, 4, 198–207, doi:10.3762/bjnano.4.20

• of the second phase contrast to material properties in the small-amplitude regime. This method, which was later implemented experimentally [3] and studied further theoretically and computationally [4][5], gave birth to a new host of multifrequency AFM techniques, which nowadays include a wide variety

High-resolution dynamic atomic force microscopy in liquids with different feedback architectures

• John Melcher,
• David Martínez-Martín,
• Miriam Jaafar,
• Julio Gómez-Herrero and
• Arvind Raman

Beilstein J. Nanotechnol. 2013, 4, 153–163, doi:10.3762/bjnano.4.15

• of imaging resolution and the role of feedback control in dAFM. Prior efforts to analyze imaging resolution in dAFM have typically focused on the small-amplitude limit in order to establish a relationship between various noise sources in the experimental setup and the minimum detectable gradient of

Mapping mechanical properties of organic thin films by force-modulation microscopy in aqueous media

• Jianming Zhang,
• Zehra Parlak,
• Carleen M. Bowers,
• Terrence Oas and
• Stefan Zauscher

Beilstein J. Nanotechnol. 2012, 3, 464–474, doi:10.3762/bjnano.3.53

• feedback controller of the AFM keeps the tip–sample force constant during the surface scan. In addition, however, a piezoelectric transducer in the cantilever holder was used to excite the cantilever with a small amplitude, off-resonance frequency. A lock-in amplifier (AMETEK model 7280) was used to

Repulsive bimodal atomic force microscopy on polymers

• Alexander M. Gigler,
• Christian Dietz,
• Maximilian Baumann,
• Nicolás F. Martinez,
• Ricardo García and
• Robert W. Stark

Beilstein J. Nanotechnol. 2012, 3, 456–463, doi:10.3762/bjnano.3.52

• , however, was strongly influenced by the oscillation of the fundamental eigenmode. Nevertheless, a high amplitude setpoint ratio A1/A01 for topographical feedback should be chosen; otherwise, crosstalk can occur. Imaging with small amplitude ratios A01/A02 on stiff samples (e.g., silicon) is not stable due

Graphite, graphene on SiC, and graphene nanoribbons: Calculated images with a numerical FM-AFM

• Fabien Castanié,
• Laurent Nony,
• Sébastien Gauthier and
• Xavier Bouju

Beilstein J. Nanotechnol. 2012, 3, 301–311, doi:10.3762/bjnano.3.34

• amplitude constant and equal to a predefined setpoint. Large-amplitude (typically 10–20 nm) to small-amplitude (of the order of 0.02 nm to mimic a qPlus sensor [62]) settings are available with the n-AFM. The DC allows the regulation of the tip–sample distance based on minimizing the difference between Δf

Theoretical study of the frequency shift in bimodal FM-AFM by fractional calculus

• Elena T. Herruzo and
• Ricardo Garcia

Beilstein J. Nanotechnol. 2012, 3, 198–206, doi:10.3762/bjnano.3.22

• approximations, which are valid in the large and small amplitude limits, respectively. For A1 above 0.1 nm, the half-derivative approximation should be used, while for A1 below 0.1 nm, the derivative approximation is a good choice. Figure 5c and Figure 5d show a comparison between the numerical results obtained

• from Equation 23 and the half-integral (Equation 24) and derivative (Equation 26) approximations for the frequency shift of the first mode, which are valid in the large and small amplitude limits. When A1 is above 0.4 nm, the half-integral approximation can be used, while the derivative approximation

qPlus magnetic force microscopy in frequency-modulation mode with millihertz resolution

• Maximilian Schneiderbauer,
• Daniel Wastl and
• Franz J. Giessibl

Beilstein J. Nanotechnol. 2012, 3, 174–178, doi:10.3762/bjnano.3.18

• fork. The qPlus sensor [8] is based on a quartz tuning fork, in which one prong is attached to a carrier substrate. The large spring constant of the qPlus, k = 1800 Nm−1, allows one to overcome the snap-to-contact-problem in small-amplitude operation [9]. In this mode, the qPlus setup is customized for

• small amplitude for the topographic path and a large one for the magnetic path. In our current setup, the same amplitude is used for both paths. For FM detection we utilized the Nanonis OC4 and Nanosurf Saphyr, both of which are fully digital, allowing lowest noise operation. As a reference sample we

Effect of the tip state during qPlus noncontact atomic force microscopy of Si(100) at 5 K: Probing the probe

• Adam Sweetman,
• Sam Jarvis,
• Rosanna Danza and
• Philip Moriarty

Beilstein J. Nanotechnol. 2012, 3, 25–32, doi:10.3762/bjnano.3.3

• changes at the tip apex can be responsible for the altered tip–sample interaction. Conclusion In conclusion we have presented data demonstrating a wide range of stable image types in the small-amplitude NC-AFM of the Si(100) surface at 5 K. We have shown that the qualitative and quantitative behaviour of