Cantilever signature of tip detachment during contact resonance AFM

• Devin Kalafut,
• Ryan Wagner,
• Maria Jose Cadena,
• Anil Bajaj and
• Arvind Raman

Beilstein J. Nanotechnol. 2021, 12, 1286–1296, doi:10.3762/bjnano.12.96

Application of contact-resonance AFM methods to polymer samples

• Sebastian Friedrich and
• Brunero Cappella

Beilstein J. Nanotechnol. 2020, 11, 1714–1727, doi:10.3762/bjnano.11.154

• Sebastian Friedrich Brunero Cappella Federal Institute for Material Research and Testing (BAM), Unter den Eichen 87, 12205 Berlin, Germany 10.3762/bjnano.11.154 Abstract Contact-resonance AFM (CR-AFM) has been used in recent years for the measurement of mechanical properties of rather stiff

• phase image. The resulting contrast is, however, hard to analyze quantitatively. Contact-resonance AFM (CR-AFM) [4][5] is a dynamic contact technique that makes use of the vibrational behavior of the cantilever while the tip is in permanent contact with the sample. Generally, an increase in sample

• CR frequencies can be directly fitted to estimate the elastic modulus, without calculation of the sample stiffness and without the use of a calibration sample. Advantages and limitations of CR techniques are elucidated, with focus on polymer samples. Theory The central goal of contact-resonance AFM

On the frequency dependence of viscoelastic material characterization with intermittent-contact dynamic atomic force microscopy: avoiding mischaracterization across large frequency ranges

• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 1409–1418, doi:10.3762/bjnano.11.125

• response of the cantilever with respect to the excitation, within amplitude-modulation AFM (AM-AFM)), which generally yields high-contrast images for dissipative materials [22]. Dynamic contact-mode techniques such as contact-resonance AFM [11][12][13][28], dual-amplitude resonance tracking AFM (DART [10

Scanning speed phenomenon in contact-resonance atomic force microscopy

• Christopher C. Glover,
• Jason P. Killgore and
• Ryan C. Tung

Beilstein J. Nanotechnol. 2018, 9, 945–952, doi:10.3762/bjnano.9.87

• contact-resonance frequency is observed with increasing scan speed. Proper characterization and understanding of this phenomenon is necessary to conduct accurate quantitative imaging using contact-resonance AFM, and other contact-mode AFM techniques, at higher scan speeds. A squeeze film hydrodynamic

Material discrimination and mixture ratio estimation in nanocomposites via harmonic atomic force microscopy

• Weijie Zhang,
• Yuhang Chen,
• Xicheng Xia and
• Jiaru Chu

Beilstein J. Nanotechnol. 2017, 8, 2771–2780, doi:10.3762/bjnano.8.276

• mode and contact resonance AFM have their own features and ideal conditions [11][12][13]. For example, the phase signal in tapping AFM carries certain information on the mechanical properties. Such a mode reduces sample damage and allows softer materials to be nondestructively scanned. However, the

• modulation and resonance frequency in contact resonance AFM are used to extract the mechanical properties quantitatively [16][17]. However, the continuous tip–sample contact may cause severe sample damage or tip wear. In tapping mode, the tip can touch the sample periodically. Due to the nonlinear contact

• harmonic amplitude image is quite similar to that observed in contact resonance AFM. Further details can be found in [35]. In the quantitative mapping of the harmonic response to the local elastic properties this factor has to be taken into account. Owing to the complexity in each influencing factor, the

Material property analytical relations for the case of an AFM probe tapping a viscoelastic surface containing multiple characteristic times

• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 2230–2244, doi:10.3762/bjnano.8.223

• materials is usually performed through contact-mode methods. Contact-resonance AFM, force-modulation AFM and static force spectroscopy are the most popular examples in this category [9][10][11][12][13]. The permanent-contact nature of these methods offers an important advantage in mechanical

• deflection setpoint, as in contact-resonance AFM [10][31] and force-modulation AFM [11]. In addition to that displacement (deflection setpoint), a harmonic excitation is imposed. Mathematically the total tip–sample force excitation is: where Fs is the static force setpoint, H(t) is the Heaviside (unit step

• ) function, F0 is the amplitude of the harmonic excitation force, ω is the driving and response frequency, and Obviously, one has no direct control over the harmonic tip–sample force in the experiment (similar to contact-resonance AFM or force-modulation AFM), but instead, a displacement or force excitation

Relationships between chemical structure, mechanical properties and materials processing in nanopatterned organosilicate fins

• Gheorghe Stan,
• Richard S. Gates,
• Qichi Hu,
• Kevin Kjoller,
• Craig Prater,
• Kanwal Jit Singh,
• Ebony Mays and
• Sean W. King

Beilstein J. Nanotechnol. 2017, 8, 863–871, doi:10.3762/bjnano.8.88

• with contact resonance AFM (CR-AFM) [29] mechanical property measurements in the investigation of 20–500 nm wide fin structures fabricated in a nanoporous organosilicate thin film. Nanoporous organosilicates are of significant importance to the electronics industry for reducing various parasitic

• resonance AFM (CR-AFM) to investigate the fabrication of 20–500 nm wide fin structures in a nanoporous organosilicate material. We show that by combining these two techniques, one can clearly observe variations of chemical structure and mechanical properties that correlate with the fabrication process and

• molecular/chemical structure characterization has only been recently demonstrated with the advent of atomic-force-microscopy-based infrared spectroscopy (AFM-IR) and related techniques. Therefore, we have combined measurements of chemical structures with AFM-IR and of mechanical properties with contact

Nanoscale effects in the characterization of viscoelastic materials with atomic force microscopy: coupling of a quasi-three-dimensional standard linear solid model with in-plane surface interactions

• Santiago D. Solares

Beilstein J. Nanotechnol. 2016, 7, 554–571, doi:10.3762/bjnano.7.49

• contact-resonance AFM (CR-AFM) methods (including dual-amplitude resonance tracking, DART) [2][3][4][5][6], the surface is treated using a linear Kelvin–Voigt model, which consists of a linear spring in parallel with a linear damper. Linear models are used in this case because the oscillation amplitude of

A simple and efficient quasi 3-dimensional viscoelastic model and software for simulation of tapping-mode atomic force microscopy

• Santiago D. Solares

Beilstein J. Nanotechnol. 2015, 6, 2233–2241, doi:10.3762/bjnano.6.229

• continuous periodic strain is applied to the sample and the probe–sample system is in steady state, which in AFM requires a contact-mode measurement such as contact-resonance AFM (CR-AFM) [3][4][5] or dual amplitude resonance tracking (DART) [4]. When the applied strain is not continuous and periodic, and

Modeling viscoelasticity through spring–dashpot models in intermittent-contact atomic force microscopy

• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2014, 5, 2149–2163, doi:10.3762/bjnano.5.224

• physically accurate models for viscoelastic samples. On the other hand, better quantitative agreement has been accomplished through contact-mode based techniques such as contact resonance AFM (CR-AFM) [17], band excitation AFM (BE-AFM) [18][19] and dual-amplitude resonance tracking AFM (DART-AFM) [20]. These

Trade-offs in sensitivity and sampling depth in bimodal atomic force microscopy and comparison to the trimodal case

• Babak Eslami,
• Daniel Ebeling and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2014, 5, 1144–1151, doi:10.3762/bjnano.5.125

• through changes in the amplitude of the highest driven eigenmode, which has the highest dynamic force constant (the higher stiffness of higher eigenmodes has also been advantageous in subsurface imaging applications in contact resonance AFM [18]). In this paper we show that indentation depth modulation

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

• is provided. Keywords: contact-resonance AFM; dynamic AFM; frequency modulation; phase-locked loop; viscoelasticity; Introduction A number of atomic force microscopy (AFM) variants have emerged since the introduction of the original technique in 1986 [1]. Besides topographical acquisition and

• acoustic microscopy (AFAM) configuration [3]), such that the tip oscillation amplitude and its phase with respect to the excitation can be measured and converted into a loss and storage modulus. In contact resonance AFM (CR-AFM) [3][4][5][6][7][8][9] a similar setup is used, supplying the sinusoidal

• cleaner spectra at the expense of a more aggressive tip–sample coupling. Conclusion The resonance frequency, amplitude, and phase of the first two eigenmodes of two contact resonance AFM (CR-AFM) configurations, namely a setup with sample stage excitation (AFAM) and one with cantilever base excitation

Towards 4-dimensional atomic force spectroscopy using the spectral inversion method

• Jeffrey C. Williams and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2013, 4, 87–93, doi:10.3762/bjnano.4.10

• folding/unfolding. For example, it should be possible to develop methods for fitting experimental data to increasingly elaborate viscoelastic models that go beyond the Kelvin–Voigt model used in the current state of the art in contact-resonance AFM [15][16]. In particular, the Kelvin–Voigt model is not

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

• microscopy (AFAM) [31], and contact resonance AFM (CR-AFM) [32][33][34][35], contact resonance frequencies are deliberately chosen to enhance the imaging sensitivity. However, acoustic AFM imaging in solution is challenging since the liquid phase complicates the cantilever dynamics through fluid damping. To

• of a quantitative viscoelastic modeling approach in liquids, in analogy to those developed for contact resonance AFM in air [32][33]. Results and Discussion FMM working principles Linear regime in FMM In FMM, the cantilever tip contacts the substrate surface with a constant static force while a small

Scanning probe microscopy and related methods

• Ernst Meyer

Beilstein J. Nanotechnol. 2010, 1, 155–157, doi:10.3762/bjnano.1.18

• optical microscopy, SNOM: Scanning nearfield optical microscopy, TSM: Thermal scanning microscopy, cr-AFM: contact-resonance AFM, SPSTM: Spin polarized STM, SHPM: Scanning Hall probe microscopy, SGM: Scanning gate microscopy, SVM: Scanning voltage microscopy / Nanopotentiometry, ESR-STM: Electron spin