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

Advanced scanning probe lithography using anatase-to-rutile transition to create localized TiO₂ nanorods

• Julian Kalb,
• Vanessa Knittel and
• Lukas Schmidt-Mende

Beilstein J. Nanotechnol. 2019, 10, 412–418, doi:10.3762/bjnano.10.40

• probe lithography was performed with an Innova AFM (Bruker) in contact mode. The applied force was significantly higher than usually chosen for topography scanning. We used OTESPA-R3 (Bruker AFM probes) silicon tips with a spring constant of approximately 26 N/m. Based on the spring constant, we

• . This is related to the high refractive index of TiO2, the size of the nanorods, and the dielectric antenna effect of the stringed nanorods [46]. To test the reliability of the presented method, the writing process was repeated with several probes. The spring constant is different for each probe even if

• they are taken from the same fabrication batch. The value range for the spring constant given by the manufacturer is 12–103 N/m, which results in a value range for the applied force of 4–32 μN. However, the spring constants of the used probes have been usually in the lower third of the given range. It

Threshold voltage decrease in a thermotropic nematic liquid crystal doped with graphene oxide flakes

• Mateusz Mrukiewicz,
• Krystian Kowiorski,
• Paweł Perkowski,
• Rafał Mazur and
• Małgorzata Djas

Beilstein J. Nanotechnol. 2019, 10, 71–78, doi:10.3762/bjnano.10.7

• (Figure 2a). This technique can provide qualitative and quantitative information about tested samples [31][32][33]. To register topographical maps, silicon AC240 TS (Olympus) scanning probes were used in a frequency range from 0.8 to 1.0 Hz. The nominal probe spring constant was 2.7 N/m and the radius was

Electrostatic force microscopy for the accurate characterization of interphases in nanocomposites

• Diana El Khoury,
• Richard Arinero,
• Jean-Charles Laurentie,
• Mikhaël Bechelany,
• Michel Ramonda and
• Jérôme Castellon

Beilstein J. Nanotechnol. 2018, 9, 2999–3012, doi:10.3762/bjnano.9.279

• the topography profile acquired during the first scan. An AC voltage was then applied between the probe and the sample holder. Furthermore, the mechanical oscillation amplitude was reduced to stay in the linear regime. The detected electrostatic force gradients reduced the effective spring constant of

Size limits of magnetic-domain engineering in continuous in-plane exchange-bias prototype films

• Alexander Gaul,
• Daniel Emmrich,
• Timo Ueltzhöffer,
• Henning Huckfeldt,
• Hatice Doğanay,
• Johanna Hackl,
• Muhammad Imtiaz Khan,
• Daniel M. Gottlob,
• Gregor Hartmann,
• André Beyer,
• Dennis Holzinger,
• Slavomír Nemšák,
• Claus M. Schneider,
• Armin Gölzhäuser,
• Günter Reiss and
• Arno Ehresmann

Beilstein J. Nanotechnol. 2018, 9, 2968–2979, doi:10.3762/bjnano.9.276

• the MFM measurements. Hard magnetic MFM probes (Nanosensors PPP-MFMR) with a nominal resonance frequency of 70 kHz and a spring constant of 2.8 N·m−1 were employed. XPEEM characterization XPEEM measurements [48][49] of the local magnetization distribution in the F layer of the EB layer system were

In situ characterization of nanoscale contaminations adsorbed in air using atomic force microscopy

• Jesús S. Lacasa,
• Lisa Almonte and
• Jaime Colchero

Beilstein J. Nanotechnol. 2018, 9, 2925–2935, doi:10.3762/bjnano.9.271

• force gradient) induced by an alternating bias between tip and sample (also termed FM detection of electrostatic force). This frequency shift is: where C″(d) is the second derivative of the capacitance, ν0 is the (free) resonance frequency and clever is the spring constant of the cantilever. For a bias

Characterization of the microscopic tribological properties of sandfish (Scincus scincus) scales by atomic force microscopy

• Weibin Wu,
• Christian Lutz,
• Simon Mersch,
• Richard Thelen,
• Christian Greiner,
• Guillaume Gomard and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2018, 9, 2618–2627, doi:10.3762/bjnano.9.243

• to the scales before imaging. Spring constant and deflection sensitivity of all cantilevers (All-in-One-Al, BudgetSensors) were determined with the thermal tune method integrated into the corresponding AFM software. Normal load and lateral force were calibrated according to the procedure described by

• cantilevers (spring constant of approx. 40 N/m) and sharp silicon tips. Nine areas (5 µm × 5 µm) were scratched on each sample with increasing load or fixed load and increasing time. Every experiment was started with a pristine sharp tip cantilever. The red rectangles mark areas where no wear was observed

Effective sensor properties and sensitivity considerations of a dynamic co-resonantly coupled cantilever sensor

• Julia Körner

Beilstein J. Nanotechnol. 2018, 9, 2546–2560, doi:10.3762/bjnano.9.237

• and the degree of frequency matching. Consequently, while an individual cantilever is characterized by its eigenfrequency, spring constant, effective mass and quality factor, the resonance peaks of the co-resonantly coupled system can be described by effective properties which are a mixture of both

• -resonant system’s effective properties. While the effective spring constant and effective mass mainly define the sensitivity of the coupled cantilever sensor, the effective quality factor primarily influences the detectability. Hence, a balance has to be found in optimizing both parameters in sensor design

• . These properties can be altered either due to a change of the cantilever’s properties (spring constant, mass) or an external force gradient. The oscillation detection is usually realized by laser-optical methods such as interferometry or deflectometry [8]. In many cases, the shift of the cantilever’s

High-throughput micro-nanostructuring by microdroplet inkjet printing

• Hendrikje R. Neumann and
• Christine Selhuber-Unkel

Beilstein J. Nanotechnol. 2018, 9, 2372–2380, doi:10.3762/bjnano.9.222

• processing Atomic force microscopy (AFM) topographic imaging was employed to measure the roughness of the samples. Imaging was performed on a JPK NanoWizard 3 (JPK Instruments AG) operated in ac mode using ACTA cantilevers (spring constant ≈40 N/m, resonance frequency ≈300 kHz; Applied NanoStructuresInc

Nanoscale characterization of the temporary adhesive of the sea urchin Paracentrotus lividus

• Ana S. Viana and
• Romana Santos

Beilstein J. Nanotechnol. 2018, 9, 2277–2286, doi:10.3762/bjnano.9.212

• at a scan rate of ≈1.0 Hz, in ambient conditions (≈21 °C), using a ScanAsyst-air probe (Bruker) with a spring constant of 0.44 N/m. Images obtained in filtered artificial seawater were carried out in a fluid cell using either a ScanAsyst-fluid probe (Bruker) with a spring constant of 1.12 N/m or a

• silicon nitride cantilever with a silicon tip (SNL, Bruker) with a spring constant of 0.12 N/m. All of the above-mentioned probes were calibrated on a stiff sample, to access tip deflection sensitivity, followed by thermal tuning to determine the spring constant. At least five sea urchin adhesive

The structural and chemical basis of temporary adhesion in the sea star Asterina gibbosa

• Birgit Lengerer,
• Marie Bonneel,
• Mathilde Lefevre,
• Elise Hennebert,
• Philippe Leclère,
• Emmanuel Gosselin,
• Peter Ladurner and
• Patrick Flammang

Beilstein J. Nanotechnol. 2018, 9, 2071–2086, doi:10.3762/bjnano.9.196

• . Silicon tips (NCH, Bruker Nano Inc) were calibrated on a stiff surface prior to experiments in order to quantify the tip–sample forces. The resonance frequency is about 320 kHz and their spring constant (determined by thermal tuning) is about 40 N/m. All the images were recorded with a resolution of 512

Quantitative comparison of wideband low-latency phase-locked loop circuit designs for high-speed frequency modulation atomic force microscopy

• Kazuki Miyata and
• Takeshi Fukuma

Beilstein J. Nanotechnol. 2018, 9, 1844–1855, doi:10.3762/bjnano.9.176

• cantilever thermal vibrations nth. These values were calculated using the following equation [1][33]: where kB, T, k, and A denote Boltzmann's constant, the absolute temperature, the cantilever spring constant, and the cantilever vibration amplitude, respectively. Qd* represents the apparent Q-factor in the

Know your full potential: Quantitative Kelvin probe force microscopy on nanoscale electrical devices

• Amelie Axt,
• Ilka M. Hermes,
• Victor W. Bergmann,
• Niklas Tausendpfund and
• Stefan A. L. Weber

Beilstein J. Nanotechnol. 2018, 9, 1809–1819, doi:10.3762/bjnano.9.172

• force field Fts(z) causes a shift in the angular resonance frequency ω0 of the cantilever. For small oscillation amplitudes, the modified angular resonance frequency can approximately be described by means of an effective spring constant where k is the undisturbed spring constant of the cantilever

• Asylum research MFP3D SFM in a nitrogen glovebox (level of humidity below 1%) for all experiments. The typical resonance frequency of the cantilevers (Bruker Model:SCM-PIT-V2) was ≈75 kHz, spring constant of 3 N/m, a tip radius of 25 nm and a tip height of 10 to 15 μm. The typical length of the

Friction force microscopy of tribochemistry and interfacial ageing for the SiO_x/Si/Au system

• Christiane Petzold,
• Marcus Koch and
• Roland Bennewitz

Beilstein J. Nanotechnol. 2018, 9, 1647–1658, doi:10.3762/bjnano.9.157

• sample preparation Friction force microscopy experiments were performed with uncoated (“SiOx/Si”) and gold-coated (“Au/Si”) silicon tips and cantilevers with a nominal spring constant of knom = 0.2 N/m (PPP-CONTR, PPP-CONTAu; Nanosensors, Switzerland). The cantilevers were fixed with conductive glue

• . The holder was then transferred into the measurement chamber with the FFM experiment. Normal and lateral spring constant of each cantilever were calculated from the resonance frequency and the dimensions of cantilevers and tips. The tip height was assessed individually from SEM images of 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

• 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

Electrostatically actuated encased cantilevers

• Benoit X. E. Desbiolles,
• Gabriela Furlan,
• Adam M. Schwartzberg,
• Paul D. Ashby and
• Dominik Ziegler

Beilstein J. Nanotechnol. 2018, 9, 1381–1389, doi:10.3762/bjnano.9.130

• , and a quality factor of Q = 50.0. Using the Sader method [25] we find a spring constant of kdyn = 18 N·m−1. Figure 2d compares electrostatically excited resonance peaks for air and deionized water. For regular cantilevers without an encasement viscous losses to the surrounding medium are the dominate

Artifacts in time-resolved Kelvin probe force microscopy

• Sascha Sadewasser,
• Nicoleta Nicoara and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2018, 9, 1272–1281, doi:10.3762/bjnano.9.119

• a C code. The cantilever tip dynamics are governed by the equation of motion: where m is the effective mass, z the vertical tip position above the sample surface (z = 0), t is the time, k the effective spring constant of the cantilever, ω the natural angular frequency of the cantilever, and Q the

Electrostatic force spectroscopy revealing the degree of reduction of individual graphene oxide sheets

• Yue Shen,
• Ying Wang,
• Yuan Zhou,
• Chunxi Hai,
• Jun Hu and
• Yi Zhang

Beilstein J. Nanotechnol. 2018, 9, 1146–1155, doi:10.3762/bjnano.9.106

• force gradients cause shifts of Δf0 in the resonance frequency with a proportional relationship [30]: where k is the stiffness (or spring constant) of the cantilever. Resonance shifts also give rise to phase shifts, ∆φ, used to generate an image of the electric force gradients. In EFM imaging, the

• cantilever coating with a 10 nm Pt layer on a 20 nm Ti sublayer with a nominal spring constant of ≈3.5 Nm−1 and oscillating frequencies of 60–90 kHz. The lift start height and lift scan height in EFM imaging were 20 nm and 15 nm, respectively. Characterizing the degree of reduction of GO sheets reduced using

A simple extension of the commonly used fitting equation for oscillatory structural forces in case of silica nanoparticle suspensions

• Sebastian Schön and
• Regine von Klitzing

Beilstein J. Nanotechnol. 2018, 9, 1095–1107, doi:10.3762/bjnano.9.101

• ) serving as colloidal probe. The spring constant of the cantilever was determined via the thermal noise method [62]. The surface of the colloidal probe and the silicon wafer form the two confining walls for the experiment. As the colloidal probe is orders of magnitude larger than their distance, the forces

• % and the decay length by 2.6%. The differences are related to changes in the contact area of the colloidal probe and/or errors in the determination of the cantilever spring constant. Hence, the wavelength is unaffected by this. For this reason all experiments were conducted with a single cantilever

• movement of the z-piezo in nanometers. The data were analyzed as follows: 1) Force and separation were calculated using the sensitivity slope of the linear contact region and the spring constant of the cantilever, which is determined from the thermal spectrum. 2) All force curves were aligned in relation

Electro-optical interfacial effects on a graphene/π-conjugated organic semiconductor hybrid system

• Karolline A. S. Araujo,
• Luiz A. Cury,
• Matheus J. S. Matos,
• Thales F. D. Fernandes,
• Luiz G. Cançado and
• Bernardo R. A. Neves

Beilstein J. Nanotechnol. 2018, 9, 963–974, doi:10.3762/bjnano.9.90

• modeled by where, ω0 and k are the cantilever’s resonant frequency and spring constant, respectively, C´´(z) is the second derivative of the tip–sample capacitance C(z), Vtip is the applied bias, Φ is the tip–sample surface potential difference, and f´(z) is the first derivative of the electric force

• used for morphological (bare tip) and electrical characterization (Au-coated tips), respectively. The ScanAsyst-Air probes have typical resonant frequency ω0 = 70 kHz and a spring constant k = 0.4 N/m. During operation in peak force mode, they are oscillated at a frequency f = 2 kHz with a typical

• amplitude A = 2 nm [64]. The HQ:NSC18/Cr-Au and HQ:CSC37-CrAu probes have typical resonant frequencies ω0 = 75 kHz and ω0 = 20 kHz; and a spring constant k = 2.8 N/m and k = 0.3 N/m, respectively. For tapping and EFM imaging, these probes are oscillated near their resonant frequency with amplitude A ≈ 20 nm

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

• cyanoacrylate. A razor blade was then used to cleave the sample, leaving behind a pristine sample surface. The sample was placed in a closed AFM flow-cell with an integrated relative humidity sensor. A cantilever with spring constant kL = 1.7 ± 0.2 N/m and first free resonance = 61.85 ± 0.1 kHz was mounted to