Exploring surface charge dynamics: implications for AFM height measurements in 2D materials

• Mario Navarro-Rodriguez,
• Andres M. Somoza and
• Elisa Palacios-Lidon

Beilstein J. Nanotechnol. 2024, 15, 767–780, doi:10.3762/bjnano.15.64

• [30]. This issue can be addressed with Kelvin probe force microscopy (KPFM). Under ambient conditions, the most common mode is amplitude modulation (AM-AFM), which uses the oscillation amplitude reduction as the input for the topography feedback. Its main aspects are summarized in [31]. At large free

Effect of repeating hydrothermal growth processes and rapid thermal annealing on CuO thin film properties

• Monika Ozga,
• Eunika Zielony,
• Aleksandra Wierzbicka,
• Anna Wolska,
• Marcin Klepka,
• Marek Godlewski,
• Bogdan J. Kowalski and
• Bartłomiej S. Witkowski

Beilstein J. Nanotechnol. 2024, 15, 743–754, doi:10.3762/bjnano.15.62

• resolution of 256 × 256 pixels presented in the paper were derived from the “SCM data” channel. Contact potential difference (VCPD) measurements were carried out using Kelvin probe force microscopy (KPFM) in amplitude modulation mode, also employing SCM-PIT-V2 probes from Bruker. These measurements were

Design, fabrication, and characterization of kinetic-inductive force sensors for scanning probe applications

• August K. Roos,
• Ermes Scarano,
• Elisabet K. Arvidsson,
• Erik Holmgren and
• David B. Haviland

Beilstein J. Nanotechnol. 2024, 15, 242–255, doi:10.3762/bjnano.15.23

• amplitude modulation AFM (AM-AFM) and frequency modulation AFM (FM-AFM). Both modes, and their many variants, rely on lock-in detection of the motion signal, and in most cases, this signal is at the same frequency as the excitation. Cavity optomechanical detection principles can be used for both AM-AFM and

Exploring internal structures and properties of terpolymer fibers via real-space characterizations

• Michael R. Roenbeck and
• Kenneth E. Strawhecker

Beilstein J. Nanotechnol. 2023, 14, 1004–1017, doi:10.3762/bjnano.14.83

• N/m (nominal), k = 12–21 N/m (measured)) were used for AFM scans. By simultaneously exciting the AFM cantilever to its first and second resonance (f1 = 160–190 kHz and f2 = 900–1150 kHz, Figure 1c) and applying two distinct control conditions (amplitude modulation (AM) and frequency modulation (FM

Cross-sectional Kelvin probe force microscopy on III–V epitaxial multilayer stacks: challenges and perspectives

• Mattia da Lisca,
• José Alvarez,
• James P. Connolly,
• Nicolas Vaissiere,
• Karim Mekhazni,
• Jean Decobert and
• Jean-Paul Kleider

Beilstein J. Nanotechnol. 2023, 14, 725–737, doi:10.3762/bjnano.14.59

• sample surface. Topographical data were collected on the first pass, whereas VCPD was measured during the second one. The schematic of our KPFM setup is depicted in Figure 1. The FM-KPFM mode was chosen over the amplitude-modulation mode (AM-KPFM) since it is well known that it provides better spatial

A super-oscillatory step-zoom metalens for visible light

• Yi Zhou,
• Chao Yan,
• Peng Tian,
• Zhu Li,
• Yu He,
• Bin Fan,
• Zhiyong Wang,
• Yao Deng and
• Dongliang Tang

Beilstein J. Nanotechnol. 2022, 13, 1220–1227, doi:10.3762/bjnano.13.101

• has a specific size and could only achieve a step-like discrete phase, which, in turn, deviates from the desired phase modulation. Second, the inhomogeneous amplitude modulation also contributes to performance degradation. In our design, it is assumed that only phase modulation with uniform amplitude

Comparing the performance of single and multifrequency Kelvin probe force microscopy techniques in air and water

• Jason I. Kilpatrick,
• Emrullah Kargin and
• Brian J. Rodriguez

Beilstein J. Nanotechnol. 2022, 13, 922–943, doi:10.3762/bjnano.13.82

• transfer function of the cantilever are present in the literature and that these models may better represent the behavior of the lever in different environments [111][112][113][114][115][116]. A. Amplitude Modulation KPFM (AM) In KPFM-based techniques, a bias is applied between a conductive AFM probe and a

Direct measurement of surface photovoltage by AC bias Kelvin probe force microscopy

• Masato Miyazaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2022, 13, 712–720, doi:10.3762/bjnano.13.63

• KPFM. Moreover, AC-KPFM is applicable in both amplitude modulation and frequency modulation mode. Thus, it contributes to advancing SPV measurements in various environments, such as vacuum, air, and liquids. This method can be utilized for direct measurements of changes in surface potential induced by

• modulated signal, referring to the AC bias null method presented by Kohl and co-workers [28]. AC-KPFM avoids the problem of thermal drift and achieves a higher resolution. We provide the theory for both the amplitude modulation (AM) mode [29] and the frequency modulation (FM) mode [30] and demonstrate

Quantitative dynamic force microscopy with inclined tip oscillation

• Philipp Rahe,
• Daniel Heile,
• Reinhard Olbrich and
• Michael Reichling

Beilstein J. Nanotechnol. 2022, 13, 610–619, doi:10.3762/bjnano.13.53

• of a viscous damping layer, in-plane dissipation mechanisms have been found to cause systematic changes of the phase shift in amplitude-modulation AFM depending on the cantilever inclination [15]. Furthermore, it has been proposed to use the presence of a lateral component in the tip oscillation path

Two dynamic modes to streamline challenging atomic force microscopy measurements

• Alexei G. Temiryazev,
• Andrey V. Krayev and
• Marina P. Temiryazeva

Beilstein J. Nanotechnol. 2021, 12, 1226–1236, doi:10.3762/bjnano.12.90

• 10.3762/bjnano.12.90 Abstract The quality of topographic images obtained using atomic force microscopy strongly depends on the accuracy of the choice of scanning parameters. When using the most common scanning method – semicontact amplitude modulation (tapping) mode, the choice of scanning parameters is

• -scanner vertically, maintains A = Asp. During scanning each line, lateral movement (in the X or Y direction) is performed at a constant speed V. This is the most common dynamic mode, which is called amplitude modulation (AM-AFM) [7] and has many other names (e.g., tapping mode or semi-contact mode). The

• common feature is amplitude feedback. An alternative method uses the resonant frequency of the probe as a feedback parameter and is called frequency modulation AFM (FM-AFM). Selection of scan parameters in amplitude modulation AFM Let us consider which parameters we need to adjust in AM-AFM and what

Open-loop amplitude-modulation Kelvin probe force microscopy operated in single-pass PeakForce tapping mode

• Gheorghe Stan and
• Pradeep Namboodiri

Beilstein J. Nanotechnol. 2021, 12, 1115–1126, doi:10.3762/bjnano.12.83

• various contributions from the probe geometry and imaged features of the sample. In contrast to this, the currently implemented closed-loop (CL) variants of KPFM, either amplitude-modulation (AM) or frequency-modulation (FM), solely report on their final product in terms of the tip–sample contact

• time scale of the order of microseconds or less [29][30][31][32][33]. The most direct and easy implementations of OL-KPFM are in terms of amplitude modulation due to the intrinsic force detection that the AFM operates on. The OL-KPFM developed in this work is an AM method that performs CPD measurements

Numerical analysis of vibration modes of a qPlus sensor with a long tip

• Kebei Chen,
• Zhenghui Liu,
• Yuchen Xie,
• Chunyu Zhang,
• Gengzhao Xu,
• Wentao Song and
• Ke Xu

Beilstein J. Nanotechnol. 2021, 12, 82–92, doi:10.3762/bjnano.12.7

• than that of any tip with another diameter. Thus, 0.1 mm would be the best choice for the tip diameter. The last crucial factor to be considered is the Q factor. Lower Q factors will result in lower stability for both FM-AFM and amplitude modulation AFM (AM-AFM) [17]. As shown in Figure 9, the Q factor

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

• ][27]. Operating in ORT mode instead of amplitude-modulation AFM (AM-AFM) is particularly advantageous in vacuum, where the Q-factor of the cantilever is about one order of magnitude higher than in air. Indeed, AM-AFM imaging bandwidth is inversely proportional to the Q-factor [28] and is therefore

Current measurements in the intermittent-contact mode of atomic force microscopy using the Fourier method: a feasibility analysis

• Berkin Uluutku and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 453–465, doi:10.3762/bjnano.11.37

• Fourier analysis to implement ICM current measurements. Fourier analysis is commonly used in ICM-AFM experiments due to the periodic nature of the cantilever excitation and response. For example, in amplitude-modulation AFM (AM-AFM), the most common ICM-AFM method, a lock-in amplifier is used to track the

A review of demodulation techniques for multifrequency atomic force microscopy

• David M. Harcombe,
• Michael G. Ruppert and
• Andrew J. Fleming

Beilstein J. Nanotechnol. 2020, 11, 76–91, doi:10.3762/bjnano.11.8

• technique is performed, the demodulator is an essential component for acquiring observables to characterize the sample. Previously, the authors conducted an in-depth comparison of conventional and novel demodulation techniques for single-frequency amplitude-modulation atomic force microscopy [28]. It was

• unity amplitudes, then amplitude-modulation of a distinct frequency component at ωi is described by Here, M is the modulation index, which for AM signals is the ratio of the peak value of the modulated signal relative to the carrier. Equation 5 shows that the modulation process creates distinct

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

• Abstract Employing polymer cantilevers has shown to outperform using their silicon or silicon nitride analogues concerning the imaging speed of atomic force microscopy (AFM) in tapping mode (intermittent contact mode with amplitude modulation) by up to one order of magnitude. However, tips of the

• amplitude modulation AFM (HS-AM-AFM) enhanced by up to one order of magnitude due to their low mechanical quality factor (Q-factor) and hence their high mechanical bandwidth [23]. A tip made of SU8 or other structural polymers can be integrated into a polymer cantilever by moulding. Such tips have been

• and to increase the detection speed and sensitivity. The detection speed in amplitude-modulation mode is determined by the amplitude response time of the cantilever. The tapping-mode bandwidth is given by BW = πf0/Q, where f0 is the resonance frequency and Q is the Q-factor [32]. The resonance

Kelvin probe force microscopy work function characterization of transition metal oxide crystals under ongoing reduction and oxidation

• Dominik Wrana,
• Karol Cieślik,
• Wojciech Belza,
• Christian Rodenbücher,
• Krzysztof Szot and
• Franciszek Krok

Beilstein J. Nanotechnol. 2019, 10, 1596–1607, doi:10.3762/bjnano.10.155

• [9] or Ti/TiOx/Ti memristive devices [10]. Of the two KPFM operation modes, frequency modulation (FM) has proven to be more suitable for the investigation of oxide nanostructures (due to the higher lateral resolution) as compared to amplitude modulation (AM) [11]. Therefore, in our study, we present

Charged particle single nanometre manufacturing

• Philip D. Prewett,
• Cornelis W. Hagen,
• Claudia Lenk,
• Steve Lenk,
• Marcus Kaestner,
• Tzvetan Ivanov,
• Ahmad Ahmad,
• Ivo W. Rangelow,
• Xiaoqing Shi,
• Stuart A. Boden,
• Alex P. G. Robinson,
• Dongxu Yang,
• Sangeetha Hari,
• Marijke Scotuzzi and
• Ejaz Huq

Beilstein J. Nanotechnol. 2018, 9, 2855–2882, doi:10.3762/bjnano.9.266

• found in [154][155]. Atomic force microscopy relies on the actuation of the cantilever while simultaneously measuring the deflection [154]. Therefore, the tip–sample distance is regulated to keep the oscillation amplitude (amplitude-modulation AFM) or phase (phase-modulation AFM) at a pre-defined set

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

• (Bruker Nano Inc., Santa Barbara, CA) using AFM in tapping mode. Tapping mode AFM was performed in amplitude modulation mode. The height of the cantilever position is constantly adjusted (via a feedback loop) to keep constant the ratio of the tip vibrational amplitude in contact with the sample surface to

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

• enables atomic-scale measurements to be performed in vacuum and in liquids, its imaging speed is relatively slow (ca. 1 min/frame). High-speed amplitude modulation AFM has been developed [23] and employed to visualize the dynamic behavior of biomolecules in liquids at 10–100 ms/frame [24]. However, its

Numerical analysis of single-point spectroscopy curves used in photo-carrier dynamics measurements by Kelvin probe force microscopy under frequency-modulated excitation

• Pablo A. Fernández Garrillo,
• Benjamin Grévin and
• Łukasz Borowik

Beilstein J. Nanotechnol. 2018, 9, 1834–1843, doi:10.3762/bjnano.9.175

• values of both the CPD in dark conditions and under continuous wave illumination. Figure 9 shows an example of the obtained result when implementing this protocol over a nano-phase segregated PDBSTQx/PC71BM blend with amplitude modulation FMI-KPFM. In this case, the sample was optically excited using a

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

• amplifier. Thereby, two different detection methods can be used: The amplitude modulation (AM) mode tracks variations in the response amplitude, whereas frequency modulation (FM) mode tracks variations in the cantilever’s resonance frequency, e.g., via the phase lag between excitation and response. By

• cantilevers was ≈225 μm, the width ≈35 μm. Tip, tip cone and cantilever are coated with PtIr (work function 5.5 eV [39]) on both sides. The topography feedback was performed with amplitude modulation (AM) on the first eigenmode and the oscillation amplitude was kept to approximately 40 nm for all methods. To

• modulation KPFM (FM sideband) scans in single pass with VAC of 3 V [7]. The CPD line profiles in b) were extracted from amplitude modulation KPFM (AM lift mode) scans in lift mode with a tip–sample distance of 10 nm, an oscillation amplitude of ≈80 nm and a tip voltage UAC of 1 V. Each line profile is an

Excitation of nonradiating magnetic anapole states with azimuthally polarized vector beams

• Aristeidis G. Lamprianidis and
• Andrey E. Miroshnichenko

Beilstein J. Nanotechnol. 2018, 9, 1478–1490, doi:10.3762/bjnano.9.139

• introduced: the field intensity at the vicinity of the focal spot drops to less than a third. Nonetheless, one could potentially come up with more efficient ways of shaping the multipolar content of the excitation, i.e., more complex illumination schemes that can also include amplitude modulation or multiple

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

• an annealed ultra-flat gold surface. The surface is imaged in tapping mode using harmonic excitation with amplitude modulation feedback, a free amplitude of 1 nm and a set-point of 0.8 nm. In harmonic excitation, we observe that intentional switching of the applied Udc by a few volts would result in

• ) Topographic image of copper grains evaporated onto an annealed ultra-flat gold surface. The image is recorded in air using electrostatic excitation with amplitude modulation feedback and a free amplitude of 1 nm and set-point of 0.8 nm. a) Oscillation amplitude at the resonance frequency of the cantilever