A cantilever-based, ultrahigh-vacuum, low-temperature scanning probe instrument for multidimensional scanning force microscopy

• Hao Liu,
• Zuned Ahmed,
• Sasa Vranjkovic,
• Manfred Parschau,
• Andrada-Oana Mandru and
• Hans J. Hug

Beilstein J. Nanotechnol. 2022, 13, 1120–1140, doi:10.3762/bjnano.13.95

• sphere running on a hardened steel plate. Note that initially a sapphire plate was used. However, we found the plate cracked after a few days of piezo motor operation, presumably caused from an ultrasound-actuated contact resonance of the Al2O3 sphere on the sapphire plate arising from the triangular

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

• Devin Kalafut Ryan Wagner Maria Jose Cadena Anil Bajaj Arvind Raman School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA 10.3762/bjnano.12.96 Abstract Contact resonance atomic force microscopy, piezoresponse force microscopy, and electrochemical strain microscopy are

• connect the qualitative and quantitative behavior to experimental features. Keywords: atomic force microscopy (AFM); contact resonance; nonlinear normal mode (NNM); tip–sample detachment; photothermal excitation; Introduction Contact resonance atomic force microscopy (CR-AFM) [1][2], piezoresponse force

• the first contact resonance frequency. With increasing drive amplitude, the response amplitude of the resonance peak increases, but the frequency of the resonance peak decreases, that is, a nonlinear softening effect. Once a certain drive amplitude threshold is crossed (approx. 3.0 mW photothermal

The role of convolutional neural networks in scanning probe microscopy: a review

• Ido Azuri,
• Irit Rosenhek-Goldian,
• Neta Regev-Rudzki,
• Georg Fantner and
• Sidney R. Cohen

Beilstein J. Nanotechnol. 2021, 12, 878–901, doi:10.3762/bjnano.12.66

• conditions for band-excitation piezoresponse force microscopy (PFM) [134]. Band excitation collects a band of frequencies around the contact resonance frequency of the tip–sample system, which is modeled by a simple harmonic oscillator equation. This allows for the determination of several physical

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

• . Keywords: atomic force microscopy; contact resonance; mechanical properties; polymers; wear; Introduction The development of new materials for applications on the nanoscale, such as thin polymer films, demands a reliable determination of their mechanical properties. Atomic force microscopy (AFM) is a very

• 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

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

An atomic force microscope integrated with a helium ion microscope for correlative nanoscale characterization

• Santiago H. Andany,
• Gregor Hlawacek,
• Stefan Hummel,
• Charlène Brillard,
• Mustafa Kangül and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2020, 11, 1272–1279, doi:10.3762/bjnano.11.111

• topography of the photoresist PMMA. Many more examples can be envisioned. The He ion beam is known to change the mechanical [37], electrical [38], and magnetic properties of materials [39]. AFM can be used to measure mechanical properties using contact resonance [40][41] or off-resonance tapping techniques

Stochastic excitation for high-resolution atomic force acoustic microscopy imaging: a system theory approach

• Edgar Cruz Valeriano,
• José Juan Gervacio Arciniega,
• Christian Iván Enriquez Flores,
• Susana Meraz Dávila,
• Joel Moreno Palmerin,
• Martín Adelaido Hernández Landaverde,
• Yuri Lizbeth Chipatecua Godoy,
• Aime Margarita Gutiérrez Peralta,
• Rafael Ramírez Bon and
• José Martín Yañez Limón

Beilstein J. Nanotechnol. 2020, 11, 703–716, doi:10.3762/bjnano.11.58

• that gives a qualitative relationship between a set of contact resonance frequencies and the indentation modulus. It is based on white-noise excitation of the tip–sample interaction and uses system theory for the extraction of the resonance modes. During conventional scanning, for each pixel, the tip

• of force–displacement curves or of contact resonance frequencies. The techniques based on force–displacement curves are ideal when the stiffness of the cantilever and the sample are similar. The techniques based on contact resonance frequencies are appropriate when the stiffness of the sample

• these contact resonance frequencies. It is important to notice that a set of resonance frequencies can provide a unique value for contact stiffness according to Equation 27 in a quantitative way. For this purpose, a mapping transformation from resonance frequencies to contact stiffness was obtained

Subsurface imaging of flexible circuits via contact resonance atomic force microscopy

• Wenting Wang,
• Chengfu Ma,
• Yuhang Chen,
• Lei Zheng,
• Huarong Liu and
• Jiaru Chu

Beilstein J. Nanotechnol. 2019, 10, 1636–1647, doi:10.3762/bjnano.10.159

• , Anhui, China 10.3762/bjnano.10.159 Abstract Subsurface imaging of Au circuit structures embedded in poly(methyl methacrylate) (PMMA) thin films with a cover thickness ranging from 52 to 653 nm was carried out by using contact resonance atomic force microscopy (CR-AFM). The mechanical difference of the

• force microscopy (AFM); contact resonance atomic force microscopy (CR-AFM); contact stiffness; defect detection; flexible circuits; subsurface imaging; Introduction With the rapid shrinkage of microelectronic devices, flexible circuits are intensively used while being functionalized as supercapacitors

• ) has emerged as a promising way. Various SPM-based nanoscale subsurface imaging methods have been proposed that rely on different detection mechanisms including thermal, magnetic, electric, and mechanical sensing. Among them, contact resonance atomic force microscopy (CR-AFM) demonstrates the unique

Nanoscale spatial mapping of mechanical properties through dynamic atomic force microscopy

• Zahra Abooalizadeh,
• Leszek Josef Sudak and
• Philip Egberts

Beilstein J. Nanotechnol. 2019, 10, 1332–1347, doi:10.3762/bjnano.10.132

• modulus of highly oriented pyrolytic graphite (HOPG), specifically by using force modulation microscopy (FMM) and contact resonance (CR) AFM. In both of these techniques, a variation in the amplitude signal was observed when scanning over an uncovered step edge of HOPG. In comparison, no variation in the

• compared with no change in the elastic modulus for covered steps. The analysis of the experimental data taken under varying normal loads and with several different tips showed that the elastic modulus determination was unaffected by these parameters. Keywords: atomic force microscopy; contact resonance

• (FMM) and contact resonance (CR) AFM, will allow for the overarching goal of nanoscale mechanical property measurements to be realized. In FMM, the tip is pressed into contact with the surface and oscillated at a frequency off resonance. The obtained variations in the measured amplitude of the

Recent highlights in nanoscale and mesoscale friction

• Andrea Vanossi,
• Dirk Dietzel,
• Andre Schirmeisen,
• Ernst Meyer,
• Rémy Pawlak,
• Thilo Glatzel,
• Marcin Kisiel,
• Shigeki Kawai and
• Nicola Manini

Beilstein J. Nanotechnol. 2018, 9, 1995–2014, doi:10.3762/bjnano.9.190

• oscillation frequency in the region of the contact resonance was applied. Under these conditions, moderate voltages of a few volts are sufficient to create variations of the normal force that are sufficient to move the contact zone without measurable sticking force. Essentially, the friction control is the

Correlative electrochemical strain and scanning electron microscopy for local characterization of the solid state electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃

• Nino Schön,
• Deniz Cihan Gunduz,
• Shicheng Yu,
• Hermann Tempel,
• Roland Schierholz and
• Florian Hausen

Beilstein J. Nanotechnol. 2018, 9, 1564–1572, doi:10.3762/bjnano.9.148

• relatively new technique based on atomic force microscopy (AFM): An AC voltage with the same frequency as the contact resonance frequency of the tip–sample contact is applied to a conductive tip. [22][23]. The induced electrical field in the material under investigation is extremely localized due to the

• in some way. Topographical features lead to a change in contact area between tip and sample, which is likely to influence the signal formation process and therefore induce crosstalk as a change in contact area influences the contact resonance conditions. In order to investigate this effect in more

• mobility [22]. As cantilevers, Bruker SCM-PIT-V2 (Bruker, Camarillo, USA) cantilevers with a conductive Pt/Ir coating and a nominal spring constant of 3 N·m−1 were employed. The contact resonance frequency and the amplitude were tracked with a phase-locked loop (HF2LI, Zurich Instruments, Switzerland) [34

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

• /bjnano.9.87 Abstract This work presents data confirming the existence of a scan speed related phenomenon in contact-mode atomic force microscopy (AFM). Specifically, contact-resonance spectroscopy is used to interrogate this phenomenon. Above a critical scan speed, a monotonic decrease in the recorded

• 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

• theory is proposed to explain this phenomenon, and model predictions are compared against the experimental data. Keywords: atomic force microscope; contact resonance; liquid; phenomenon; scan speed; Introduction With the rise in popularity of simultaneous topographic imaging and material property

A robust AFM-based method for locally measuring the elasticity of samples

• Alexandre Bubendorf,
• Stefan Walheim,
• Thomas Schimmel and
• Ernst Meyer

Beilstein J. Nanotechnol. 2018, 9, 1–10, doi:10.3762/bjnano.9.1

• elastic modulus. Δf1 and Δf2 are the frequency shifts that depend on the applied normal force, FN. They are determined from the measured contact resonances through the relation Δfi = fi − f0,i, where fi is the contact resonance of the i-th flexural mode. Herruzo et al. [7] showed that if the Young’s

• spring constants is actually limited for technical reasons. Indeed, for cantilevers with a too high spring constant, the second flexural contact resonance is out of the bandpass of the vertical deflection channel in most of the microscope heads. The analysis of the curve showed that setpoints for the

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

• interpretation of tapping phase results is rather complex because many factors may influence the results [14][15]. For force modulation and contact resonance operations, the tip is maintained in contact with the sample during the scan while the cantilever oscillations are monitored. The amplitude in force

• 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

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

• characterization. In the case of contact-resonance or force-modulation techniques, where the tip oscillates harmonically in permanent contact with the sample, a steady-state development between force and displacement is achieved, which greatly simplifies the interpretation of the observables. Furthermore its

• 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

High-stress study of bioinspired multifunctional PEDOT:PSS/nanoclay nanocomposites using AFM, SEM and numerical simulation

• Alfredo J. Diaz,
• Hanaul Noh,
• Tobias Meier and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 2069–2082, doi:10.3762/bjnano.8.207

• ), contact-resonance force microscopy (mechanical properties), and SEM combined with a variety of stress-strain AFM experiments and AFM numerical simulations (internal structure). We further study the nanoclay’s response to the application of pressure with multifrequency AFM and conductive AFM, whereby

• the AFM probe diameter. No pressure-induced changes in conductivity were observed in the clay-free polymer either. Keywords: biomimetics; conductive AFM; conductive nanocomposites; contact-resonance force microscopy; multifrequency AFM; transparent coatings; Introduction Bioinspired material designs

• fabricated by a simple solvent casting method. Nanoscale out-of-plane current is studied with conductive-AFM (C-AFM) and correlated with the film mechanical parameters obtained from contact-resonance force microscopy (CRFM). Then, high-pressure (few GPa) is applied locally to the surface by means of bimodal

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

• microscope; contact resonance; infrared spectroscopy; organosilicate; photothermal; Introduction A fundamental objective of materials science and engineering is to understand, control, and exploit the relationships between the structure of a material at various length scales and its properties in order to

• 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

• probe tip in contact with the sample. The repetition rate of the IR laser is tuned to a contact resonance of the AFM cantilever to maximize the oscillation amplitude of the cantilever. By sweeping the IR laser over the wavelengths of interest and monitoring changes in the amplitude of the AFM probe tip

Advanced atomic force microscopy techniques III

• Thilo Glatzel and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2016, 7, 1052–1054, doi:10.3762/bjnano.7.98

• Eva Roblegg and co-workers [20]. The local elastic stiffness and damping of individual phases in a titanium alloys was measured by using atomic force acoustic microscopy (AFAM) and mapping of contact-resonance spectra [21]. Another alloy, namely a Pt containing metallic glass, was characterized by AFM

Generalized Hertz model for bimodal nanomechanical mapping

• Aleksander Labuda,
• Marta Kocuń,
• Waiman Meinhold,
• Deron Walters and
• Roger Proksch

Beilstein J. Nanotechnol. 2016, 7, 970–982, doi:10.3762/bjnano.7.89

• microscope (AFM) has been used in a variety of modes to characterize micro- and nanoscale heterogeneous structures in composites and other advanced materials. The AFM can provide high resolution topographic and mechanical properties mapping using techniques such as force curves [2][3], contact resonance [4

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

• frequency of the periodic sinusoidal sample deformation, which is not well defined in a tapping-mode experiment (see [26] for a discussion of discrepancies between intermittent-contact and contact-resonance viscoelasticity measurements). Furthermore, the spectrum of the force (stress) and displacement

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

Stiffness of sphere–plate contacts at MHz frequencies: dependence on normal load, oscillation amplitude, and ambient medium

• Jana Vlachová,
• Rebekka König and
• Diethelm Johannsmann

Beilstein J. Nanotechnol. 2015, 6, 845–856, doi:10.3762/bjnano.6.87

• or another, should go to zero at small amplitudes. An explanation of the contact resonance method, which probes these relations, is given below. Deviating from this scaling prediction, the contacts usually do damp a resonance even at the smallest accessible amplitudes. This type of damping must be

• relations differ from the CM model in the details, but deciding between the two models based on the shape of the force–displacement loop is somewhat of a challenge. Interestingly, it is rather easy to distinguish between the Savkoor model and the Cattaneo–Mindlin model with the contact resonance method

• . have provided such a model [24], making extensive use of the Greenwood–Williamson formalism [25]. The experiments below rely on the contact resonance method. The contact resonance method is also applied on the macroscopic scale [26] and in AFM-based metrology [27]. In particular, the mathematics is

Mapping of elasticity and damping in an α + β titanium alloy through atomic force acoustic microscopy

• M. Kalyan Phani,
• Anish Kumar,
• T. Jayakumar,
• Walter Arnold and
• Konrad Samwer

Beilstein J. Nanotechnol. 2015, 6, 767–776, doi:10.3762/bjnano.6.79

• in the present study. The real and imaginary parts of the contact stiffness k* are obtained from the contact-resonance spectra and by using these two quantities, the maps of local elastic stiffness and the damping factor are derived. The evaluation of the data is based on the mass distribution of the

• for studying their deformation behavior, crack nucleation and propagation, dislocation activity and interaction with grain boundaries and also even helps in understanding the bulk elastic properties of multiphase materials [1][2]. Over the last two decades many contact-resonance-based atomic force

• of contact-resonance force microscopy techniques for quantitative measurements of nanomechanical properties. Ogi et al. [6] have studied elastic and damping properties in a dual-phase steel by using resonance ultrasound microscopy (RUM), which is a contact-resonance based technique but limited to

Nanometer-resolved mechanical properties around GaN crystal surface steps

• Jörg Buchwald,
• Marina Sarmanova,
• Bernd Rauschenbach and
• Stefan G. Mayr

Beilstein J. Nanotechnol. 2014, 5, 2164–2170, doi:10.3762/bjnano.5.225

• element approach (FEM). We show that the breakdown of half-space symmetry leads to an “artificial” reduction of the elastic properties of comparable lateral dimensions which overlays the effect of surface stress. Contact resonance atomic force microscopy (CR-AFM) was used to compare the simulation results

• with experiments. Keywords: finite elements; gallium nitride; indentation; mechanical properties; molecular dynamics; nanostructures; Introduction Recently developed scanning probe-based techniques, such as contact resonance atomic force microscopy (CR-AFM) [1][2], allow for the assessment of

• . Simultaneously, with continuous measurements of the contact resonance frequencies by CR-AFM, the topography image was obtained. When comparing both, the frequency and topography images, a small reduction of resonance frequency was detected near the step edge. Taking into account the diminished contact area

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