Bulk chemical composition contrast from attractive forces in AFM force spectroscopy

• Dorothee Silbernagl,
• Media Ghasem Zadeh Khorasani,
• Natalia Cano Murillo,
• Anna Maria Elert and
• Heinz Sturm

Beilstein J. Nanotechnol. 2021, 12, 58–71, doi:10.3762/bjnano.12.5

• , spring constant of the cantilever kc, and cantilever deflection δ. In this way, the forces acting on the tip are measured by recording the deflection δ of the cantilever. While decreasing the distance between the tip and the sample, the cantilever deflects toward the sample (attractive forces Fattr, −δ

• absolute value of AHam when kc is very small and JTC occurs early, before an additional deflection occurs. In the present work, cantilevers with high spring constant values are used and the effective radius Reff is unknown. Therefore, the absolute value for AHam cannot be estimated. However, the maximum

• properties of the sample can be represented by an elastic spring with a spring constant k, although this is certainly a simplification. With a cantilever deflection δ, a cantilever spring constant kc, the sample spring constant k, and a tip–sample distance Z, the elastic response of the whole setup can be

Atomic layer deposited films of Al₂O₃ on fluorine-doped tin oxide electrodes: stability and barrier properties

• Hana Krýsová,
• Michael Neumann-Spallart,
• Hana Tarábková,
• Pavel Janda,
• Ladislav Kavan and
• Josef Krýsa

Beilstein J. Nanotechnol. 2021, 12, 24–34, doi:10.3762/bjnano.12.2

• cantilever (TESPA-V2) with a resonant frequency fres of approx. 300 kHz, a spring constant k of 0.42 N·m−1, and a nominal tip radius of 8 nm (Bruker, USA) was employed. The Gwyddion software (v. 2.53) was utilized for processing AFM image data. Results and Discussion AFM was used to compare the morphology of

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

• b, density ρ, and Young’s modulus Et. The tip mass, being typically much smaller than the cantilever mass, is neglected. The tip is located at a distance L1 < L from the clamped end of the cantilever. The flexural spring constant of the cantilever is [2]. The tip–sample interaction can be modeled

• method does not offer any advantages. Like measurements through force–distance curves, such a quantitative analysis presupposes the knowledge of the tip radius and, of course, of the spring constant of the cantilever. Yet, a further parameter is needed with CR methods, namely the relative tip position γ

• curves on an uncompliant substrate, such as a silicon wafer. The spring constant could then be determined from the thermal noise spectrum [42]. Tip radii have been obtained through scanning a TGT1 test grating (NT-MDT Spectrum Instruments, Moscow, Russia) consisting of an array of sharp tips. The

Design of V-shaped cantilevers for enhanced multifrequency AFM measurements

• Mehrnoosh Damircheli and
• Babak Eslami

Beilstein J. Nanotechnol. 2020, 11, 1525–1541, doi:10.3762/bjnano.11.135

• microscopy (AFM) in soft matter characterization has expanded, the use of different types of cantilevers for these studies have also increased. One of the most common types of cantilevers used in soft matter imaging is V-shaped cantilevers due to their low normal spring constant. These types of cantilevers

• are also suitable for nanomanipulation due to their high lateral spring constants. The combination of low normal spring constant and high lateral spring constants makes V-shaped cantilevers promising candidates for imaging soft matter. Although these cantilevers are widely used in the field, there are

• , lower frequency ratios dictate lower spring constant ratios, which can be advantageous due to lower forces applied to the surface by the tip given a sufficiently high first eigenmode frequency. Finally, two commercially available V-shaped cantilevers are theoretically and experimentally benchmarked with

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

• measurements were taken using silicon piezo-resistive self-sensing cantilevers (PRS-L100-F400-SCD-PCB SCL-SensorTech Fabrication GMBH, Vienna, Austria) with a spring constant of ca. 100 N/m, and a footprint of 110 × 48 µm. Imaging gains on the custom-made controller were adjusted as high as possible before

Wet-spinning of magneto-responsive helical chitosan microfibers

• Dorothea Brüggemann,
• Johanna Michel,
• Naiana Suter,
• Matheus Grande de Aguiar and
• Michael Maas

Beilstein J. Nanotechnol. 2020, 11, 991–999, doi:10.3762/bjnano.11.83

• Figure 4. As expected, at low deformation the helical fibers behaved similarly to springs and deformed elastically (Figure 4, range I). In this elastic regime an average spring constant of 0.3 ± 0.4 N·m−1 was found (averaged over 29 fibers with average length of 9 mm). Normalized to a single fiber

• winding, the average spring constant was 2.7 ± 2.4 N·m−1. Upon further stretching and unwinding, the fiber reached the plastic regime until fully stretched (Figure 4, range II). This stretching was then followed by an elastic deformation of the unwound fiber (Figure 4, range III), which transformed to a

Extracting viscoelastic material parameters using an atomic force microscope and static force spectroscopy

• Cameron H. Parvini,
• M. A. S. R. Saadi and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 922–937, doi:10.3762/bjnano.11.77

• Mucasol, followed by IPA, and then DI water for a duration of 10 min per step. The resonant frequency and spring constant were found to be 68.953 kHz and 1.70 nN/nm, respectively. The curves are aligned as a result of the previously described conditioning steps for each velocity, and are visualized in

Quantitative determination of the interaction potential between two surfaces using frequency-modulated atomic force microscopy

• Nicholas Chan,
• Carrie Lin,
• Tevis Jacobs,
• Robert W. Carpick and
• Philip Egberts

Beilstein J. Nanotechnol. 2020, 11, 729–739, doi:10.3762/bjnano.11.60

• oscillation amplitude of the cantilever was calibrated using the procedure described in [49]. The spring constant of the cantilever was calculated using the beam geometry method [50], where the fundamental flexural resonance frequency was measured and used to determine the thickness of the cantilever. The

• length and width of the cantilever were measured using optical microscopy. In this study, the normal bending spring constant of the cantilever was determined to be 30.5 N/m with an approximate uncertainty of 10% based on the cantilever dimensions. In this study, the oscillation amplitude was set to be 12

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

• spring constant of 0.2 N/m were used. All experiments were carried out in dry air at a temperature of 21.0 ± 0.1 °C and a relative humidity of (2 ± 1)%. It is very important to define the appropriate signal to perturb the system. This allows for gathering sufficient information about the system dynamics

• compared with the fitted experimental cantilever used in this experiment. The comparison can be seen in Table 2. A commercial BudgetSensors diamond-coated silicon cantilever with 450 µm length and a spring constant of 0.2 N/m was considered. The first value was obtained from the manufacturer data, while

• observed dynamic behavior for a free AFM cantilever. Modeled values of klever. A BudgetSensors diamond-coated silicon cantilever with 450 μm length and a spring constant of 0.2 N/m was used in this experiment. Funding The work was supported by the Projects LIDTRA LN-295261 and LIDTRA LN2015-254119 of

Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique

• Matthias Simolka,
• Hanno Kaess and
• Kaspar Andreas Friedrich

Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46

• signal amplitude (R) [34]. For data acquisition, we use a National Instruments card (PCI-6111) on a separate computer controlled by a LabVIEW (R2016) routine. Electric conductive commercial tips from NT-MDT, coated with W2C with a spring constant of about 3.5 N/m and a resonance frequency of about 77 kHz

Examination of the relationship between viscoelastic properties and the invasion of ovarian cancer cells by atomic force microscopy

• Mengdan Chen,
• Jinshu Zeng,
• Weiwei Ruan,
• Zhenghong Zhang,
• Yuhua Wang,
• Shusen Xie,
• Zhengchao Wang and
• Hongqin Yang

Beilstein J. Nanotechnol. 2020, 11, 568–582, doi:10.3762/bjnano.11.45

• . Force–distance curve-based AFM measurements were carried out to calculate the optical photodiode deflection sensitivity and the cantilever spring constant was verified by the thermal noise method before experiments. MLCT cantilevers (Bruker, USA) made of silicon nitride with approximate spring constant

Atomic-resolution imaging of rutile TiO₂(110)-(1 × 2) reconstructed surface by non-contact atomic force microscopy

• Daiki Katsube,
• Shoki Ojima,
• Eiichi Inami and
• Masayuki Abe

Beilstein J. Nanotechnol. 2020, 11, 443–449, doi:10.3762/bjnano.11.35

• and a spring constant of k = 27.05 N/m. In (a), STM imaging was performed without cantilever oscillation and the parameters sample bias and current set point were 1.5 V and 50 pA, respectively. In (b), the measurement parameters were Δf = −7.9 Hz, A = 16.5 nm, and Vs = 500 mV. The white circles and

• cantilever with a resonance frequency of f0 = 154.1 kHz and a spring constant of k = 27.05 N/m. The measurement parameters were Δf = −38.1 Hz, A = 9.8 nm, and Vs = 350 mV. The asymmetric Ti2O3 model is included with the height profile in (d) for comparison of the surface geometry and the model. Area

• a resonance frequency of f0 = 154.9 kHz and a spring constant of k = 27.05 N/m. The measurement parameters were A = 10.9 nm, and Vs = 850 mV. The green and yellow regions in (b) indicate Ti2O3 rows with the left side and the right side in higher positions, respectively. Funding This work was

Nonclassical dynamic modeling of nano/microparticles during nanomanipulation processes

• Moharam Habibnejad Korayem,
• Ali Asghar Farid and
• Rouzbeh Nouhi Hefzabad

Beilstein J. Nanotechnol. 2020, 11, 147–166, doi:10.3762/bjnano.11.13

• model. They studied the effect of dimensionless load and the transition parameter on the contact area. They emphasized the importance of the MD model that covers a large area of AFM surveys [5]. Owing to the importance of the AFM cantilever spring constant and its use in calculation of the rupture force

• of protein bonds and Young’s modulus of nanoparticles, Clifford and Seah determined the AFM cantilever normal spring constant [6]. Korayem and Zakeri studied the effects of different parameters on the times and forces in a 2D manipulation. Using their proposed algorithm, the location of the

The effect of heat treatment on the morphology and mobility of Au nanoparticles

• Sven Oras,
• Sergei Vlassov,
• Simon Vigonski,
• Boris Polyakov,
• Mikk Antsov,
• Vahur Zadin,
• Rünno Lõhmus and
• Karine Mougin

Beilstein J. Nanotechnol. 2020, 11, 61–67, doi:10.3762/bjnano.11.6

• calculated with the following equation [20]: where k is the cantilever spring constant, f0 is the resonance frequency of the cantilever, Aset is the setpoint amplitude, Apiezo is the drive amplitude, θ is the phase signal and Q is the quality factor of the AFM cantilever. The dissipated power was used as a

Integration of sharp silicon nitride tips into high-speed SU8 cantilevers in a batch fabrication process

• Nahid Hosseini,
• Matthias Neuenschwander,
• Oliver Peric,
• Santiago H. Andany,
• Jonathan D. Adams and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2019, 10, 2357–2363, doi:10.3762/bjnano.10.226

• ., silicon, silicon nitride and silicon oxide), polymer cantilevers have gained attention due to their ease of fabrication, their versatility [15][16][17][18][19] and their potential for fabricating low spring constant cantilevers [20]. For instance, the microfabrication process of SU8 cantilevers has a high

• (f0) and the spring constant (k). (vi) The process is designed for top release, so the wafer is treated with DRIE to create a freestanding SU8 beam with the embedded silicon nitride tip encased in a protective oxide. (vii) The release process is finalized by placing the wafer in KOH (23% at 90 °C) to

Atomic force acoustic microscopy reveals the influence of substrate stiffness and topography on cell behavior

• Yan Liu,
• Li Li,
• Xing Chen,
• Ying Wang,
• Meng-Nan Liu,
• Jin Yan,
• Liang Cao,
• Lu Wang and
• Zuo-Bin Wang

Beilstein J. Nanotechnol. 2019, 10, 2329–2337, doi:10.3762/bjnano.10.223

• using the same parameters. The Young’s moduli of the fabricated substrates were evaluated by fitting the force–distance curves with a Hertzian cone. A probe sensor (ContAl-G, Budget Sensors) was used in the force modulation mode for measuring the Young’s moduli. The cantilever spring constant was 0.2 N

Microbubbles decorated with dendronized magnetic nanoparticles for biomedical imaging: effective stabilization via fluorous interactions

• Da Shi,
• Justine Wallyn,
• Dinh-Vu Nguyen,
• Francis Perton,
• Delphine Felder-Flesch,
• Sylvie Bégin-Colin,
• Mounir Maaloum and
• Marie Pierre Krafft

Beilstein J. Nanotechnol. 2019, 10, 2103–2115, doi:10.3762/bjnano.10.205

• frequency. Each time the tip and the sample are brought together, a force curve is captured. Ultrasharp silicon tips on a nitride lever were used (Bruker, ScanAsyst with a spring constant of 0.4 N m−1 and tip radius of ≈5 nm). During AFM imaging, the force was reduced in order to avoid dragging of molecules

Nanoarchitectonics meets cell surface engineering: shape recognition of human cells by halloysite-doped silica cell imprints

• Elvira Rozhina,
• Ilnur Ishmukhametov,
• Svetlana Batasheva,
• Farida Akhatova and
• Rawil Fakhrullin

Beilstein J. Nanotechnol. 2019, 10, 1818–1825, doi:10.3762/bjnano.10.176

• frequencies in the range of 70 to 95 kHz and spring constant in the range of 0.4 to 0.8 N m−1 (nominal length 115 µm, tip radius 2 nm) were used. The images were collected in air at 0.8–0.9 Hz scan rate and 512–1024 lines per scan. Topographic and nanomechanical characteristics were obtained. The data was

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

• stiffness gives better sensitivity as can be seen from previous discussions for the cantilever stiffness effects. Vibrating at the second mode has a significantly larger effective spring constant than the fundamental one. This leads to reduced contrast. In Figure 5d, all the experimental results of

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

• change in elastic modulus. Static indentation measurements using stiff cantilevers (≈40 N/m normal bending spring constant) were conducted and are summarized in the Appendix. These results showed that the mean elastic modulus of the HOPG terrace was 38 GPa, but could not be acquired with sufficient

Imaging the surface potential at the steps on the rutile TiO₂(110) surface by Kelvin probe force microscopy

• Masato Miyazaki,
• Huan Fei Wen,
• Quanzhen Zhang,
• Yuuki Adachi,
• Jan Brndiar,
• Ivan Štich,
• Yan Jun Li and
• Yasuhiro Sugawara

Beilstein J. Nanotechnol. 2019, 10, 1228–1236, doi:10.3762/bjnano.10.122

• cantilever deflection was measured using an optical beam deflection method [45]. The images were obtained using a commercial Ir-coated Si cantilever (NANOSENSORS) with a resonant frequency of 804 kHz and 808 kHz and a spring constant of 1500 N/m. Before the experiments, the tip was cleaned by Ar+ sputtering

Influence of dielectric layer thickness and roughness on topographic effects in magnetic force microscopy

• Alexander Krivcov,
• Jasmin Ehrler,
• Marc Fuhrmann,
• Tanja Junkers and
• Hildegard Möbius

Beilstein J. Nanotechnol. 2019, 10, 1056–1064, doi:10.3762/bjnano.10.106

• nanoparticle diameter) resulting in a positive phase shift: with A being the effective capacitive area, z the lift height, d the nanoparticle diameter, VCPD the contact potential difference between tip and substrate, Q the quality factor, k the spring constant of the cantilever, and ε0 the dielectric constant

• magnetized sphere [20][22][23]: where Q is the quality factor of the cantilever, k is the spring constant, µ0 is the vacuum permeability, mp is the magnetic moment of the nanoparticle, mtip is the magnetic moment of the tip, and a is the distance between the two dipoles and is shown schematically in Figure 5

Self-assembly and wetting properties of gold nanorod–CTAB molecules on HOPG

• Imtiaz Ahmad,
• Floor Derkink,
• Tim Boulogne,
• Pantelis Bampoulis,
• Harold J. W. Zandvliet,
• Hidayat Ullah Khan,
• Rahim Jan and
• E. Stefan Kooij

Beilstein J. Nanotechnol. 2019, 10, 696–705, doi:10.3762/bjnano.10.69

• probes (Mikromasch) with a nominal spring constant of 5–16 N/m and a resonance frequency 150–300 kHz. Drop casting A 5 μL droplet of gold nanorod suspension was deposited on a freshly cleaved HOPG surface and the solvent was left to evaporate at room temperature. After 2 h, the solvent was completely

Ultrathin hydrophobic films based on the metal organic framework UiO-66-COOH(Zr)

• Miguel A. Andrés,
• Clemence Sicard,
• Christian Serre,
• Olivier Roubeau and
• Ignacio Gascón

Beilstein J. Nanotechnol. 2019, 10, 654–665, doi:10.3762/bjnano.10.65

• . The equipment was operated in semicontact mode using a SF005&AU006NTF head. AFM data were collected using NT-MDT HA_NC(B) silicon tips with typical spring constant and resonant frequency of 3.5 N·m−1 and 140 kHz, respectively. Grazing incidence X-ray diffraction (GIXRD) characterization of films

Review of time-resolved non-contact electrostatic force microscopy techniques with applications to ionic transport measurements

• Aaron Mascaro,
• Yoichi Miyahara,
• Tyler Enright,
• Omur E. Dagdeviren and
• Peter Grütter

Beilstein J. Nanotechnol. 2019, 10, 617–633, doi:10.3762/bjnano.10.62

• the spring constant, and f0 is the resonance frequency of the oscillator. In the simplest experiment where a time-varying voltage is applied between a conducting tip and sample, C has only an explicit dependence on q and V only an explicit dependence on t: However, C does have an implicit time

• photocapacitance since the voltage is held constant over this time: where is the is the second derivative of the tip–sample capacitance with respect to vertical separation, f0 is the resonance frequency, and k0 is the spring constant. This result is derived from the relationship between the frequency shift and

• (interferometry, for example [53]) and cleaner excitation schemes such as photothermal excitation [54]. Using probes of higher stiffness, however, is not expected to be advantageous due to the inverse relationship between the measured phase shift and cantilever spring constant. Validation measurement To