Signal generation in dynamic interferometric displacement detection

• Knarik Khachatryan,
• Simon Anter,
• Michael Reichling and
• Alexander von Schmidsfeld

Beilstein J. Nanotechnol. 2024, 15, 1070–1076, doi:10.3762/bjnano.15.87

• . In a non-contact atomic force microscope (NC-AFM), it facilitates the force measurement by recording the periodic displacement of an oscillating microcantilever. To understand signal generation in a NC-AFM-based Michelson-type interferometer, we evaluate the non-linear response of the interferometer

• . Keywords: amplitude calibration; displacement detection; force microscopy; interferometer signal; NC-AFM; Introduction Optical interferometry is a reliable technique utilizing light waves to measure distance and displacement with high precision [1][2]. With the light wavelength as the length standard, a

• highly stable interferometer can detect displacements with an accuracy far beyond nanometer resolution [3], where the final physical limit is set by the photon emission statistics of the light source [4]. In non-contact atomic force microscopy (NC-AFM), interferometry is used to measure the periodic

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

• microscopy (AFM) techniques emerge as ideal tools to investigate them [26][27]. Depending on the operation mode and under controlled environmental conditions, AFM offers the possibility to record morphology along with relevant electronic, mechanical, or magnetic properties with nanoscale resolution. In

• addition, it can be integrated with classical optical spectroscopy methods such as Raman and fluorescence [20][28][29], enabling a multidimensional characterization approach. A well-recognized issue within the AFM community is the inaccurate height determination derived from topography images on

• heterogeneous samples. This discrepancy arises from various sources depending on the operation mode and working parameters. In the frequency modulation mode (FM-AFM), a non-compensated bias voltage between tip and sample, from differences in the surface potential (SP), results in inaccurate height measurements

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

• , which allowed for the investigation of both topography and electrical properties of the films. Surface topography analysis was performed by utilizing an atomic force microscopy (AFM) operating in Peak Force Tapping mode. The surface was scanned at a resolution of 1024 × 1024 measurement points using a

• effect [49][50]. Despite the measurement conditions, it was still possible to qualitatively analyze changes in surface potential and work function based on the sample preparation method. The AFM, SCM, and KPFM data were analyzed using the Nanoscope Analysis 3.0 software (Bruker). The CuO films also

• cycle one, two, and three times was conducted using SEM and AFM. Figure 3 shows representative images of the surface and height profiles (where 0 corresponds to the mean plane) acquired along the marked lines from the AFM scans of the analyzed samples. The measured parameters are compiled in Table 2

Elastic modulus of β-Ga₂O₃ nanowires measured by resonance and three-point bending techniques

• Annamarija Trausa,
• Sven Oras,
• Sergei Vlassov,
• Mikk Antsov,
• Tauno Tiirats,
• Andreas Kyritsakis,
• Boris Polyakov and
• Edgars Butanovs

Beilstein J. Nanotechnol. 2024, 15, 704–712, doi:10.3762/bjnano.15.58

• for studying the mechanical properties of NWs, such as nanoindentation [15], three-point bending tests using an atomic force microscope (AFM) [16], and in-situ scanning electron microscope (SEM) resonance [17]. However, challenges of obtaining consistent and comparable elastic modulus values across

• the length and width of NWs for three-point bending were measured in SEM, the heights were taken from the topography data obtained by AFM in the adhered parts of the NW at each end. In Figure 5a, an SEM image captures the morphology of a Ga2O3 NW positioned over an inverted pyramid structure. Notably

• , both ends of the NW are fixed, laying the foundation for a controlled three-point bending experiment. Figure 5b presents the AFM topography of the Ga2O3 NW. The loading and unloading spectra, illustrating one instance of the three-point bending test, is shown in Figure 5c. Since the elastic modulus

Enhancing higher-order modal response in multifrequency atomic force microscopy with a coupled cantilever system

• Wendong Sun,
• Jianqiang Qian,
• Yingzi Li,
• Yanan Chen,
• Zhipeng Dou,
• Rui Lin,
• Peng Cheng,
• Xiaodong Gao,
• Quan Yuan and
• Yifan Hu

Beilstein J. Nanotechnol. 2024, 15, 694–703, doi:10.3762/bjnano.15.57

• , Chinese Academy of Sciences, Dalian 116023, P. R. China 10.3762/bjnano.15.57 Abstract Multifrequency atomic force microscopy (AFM) utilizes the multimode operation of cantilevers to achieve rapid high-resolution imaging and extract multiple properties. However, the higher-order modal response of

• traditional rectangular cantilever is weaker in air, which affects the sensitivity of multifrequency AFM detection. To address this issue, we previously proposed a bridge/cantilever coupled system model to enhance the higher-order modal response of the cantilever. This model is simpler and less costly than

• , including increasing the modal frequency of the original cantilever and generating additional resonance peaks, demonstrating the significant potential of the coupled system in various fields of AFM. Keywords: atomic force microscopy; coupled system; higher-order modes; macroscale; multifrequency AFM

Gold nanomakura: nanoarchitectonics and their photothermal response in association with carrageenan hydrogels

• Nabojit Das,
• Vikas,
• Akash Kumar,
• Sanjeev Soni and
• Raja Gopal Rayavarapu

Beilstein J. Nanotechnol. 2024, 15, 678–693, doi:10.3762/bjnano.15.56

• microscopy (AFM) micrographs of CTAB-AuNM, MTAB-AuNM, and DTAB-AuNM, respectively. A total number of 50 nanoparticles were considered for the aspect ratio measurement as shown in Table 2. The analysis was performed using the ImageJ software (NIH, USA). Figure 4d–f shows AFM images of the AuNMs along with

• using TEM and AFM. Figure 4a–c showed TEM images of nanoparticles confirming the nanomakura shape. However, it was interesting to notice that the nanomakura shape is more pronounced in DTAB-AuNM. This was also confirmed using AFM considering the AuNMs under a three-dimensional view. Furthermore, 3D

• images were captured using AFM as shown in Figure 4d–f confirming the topography of AuNMs. Therefore, it was clearly observed from the complementing results obtained through TEM and AFM that the shape of the nanoparticles is makura. It can be assumed that the breaking of nanorod-shape symmetry into a

AFM-IR investigation of thin PECVD SiO_x films on a polypropylene substrate in the surface-sensitive mode

• Hendrik Müller,
• Hartmut Stadler,
• Teresa de los Arcos,
• Adrian Keller and
• Guido Grundmeier

Beilstein J. Nanotechnol. 2024, 15, 603–611, doi:10.3762/bjnano.15.51

• /bjnano.15.51 Abstract Thin silicon oxide films deposited on a polypropylene substrate by plasma-enhanced chemical vapor deposition were investigated using atomic force microscopy-based infrared (AFM-IR) nanospectroscopy in contact and surface-sensitive mode. The focus of this work is the comparison of

• the different measurement methods (i.e., contact mode and surface-sensitive mode) with respect to the chemical surface sensitivity. The use of the surface-sensitive mode in AFM-IR shows an enormous improvement for the analysis of thin films on the IR-active substrate. As a result, in this mode, the

• signal of the substrate material could be significantly reduced. Even layers that are so thin that they could hardly be measured in the contact mode can be analyzed with the surface-sensitive mode. Keywords: AFM-IR; polypropylene; surface-sensitive mode; silicon oxide; thin films; XPS; Introduction

Stiffness calibration of qPlus sensors at low temperature through thermal noise measurements

• Laurent Nony,
• Sylvain Clair,
• Daniel Uehli,
• Aitziber Herrero,
• Jean-Marc Themlin,
• Andrea Campos,
• Franck Para,
• Alessandro Pioda and
• Christian Loppacher

Beilstein J. Nanotechnol. 2024, 15, 580–602, doi:10.3762/bjnano.15.50

• University, CNRS, Centrale Marseille, FSCM (FR1739), CP2M, 13397 Marseille, France 10.3762/bjnano.15.50 Abstract Non-contact atomic force microscopy (nc-AFM) offers a unique experimental framework for topographical imaging of surfaces with atomic and/or sub-molecular resolution. The technique also permits

• little precision. An accurate stiffness calibration is therefore mandatory if accurate force measurements are targeted. In nc-AFM, the probe may either be a silicon cantilever, a quartz tuning fork (QTF), or a length extensional resonator (LER). When used in ultrahigh vacuum (UHV) and at low temperature

• the framework focuses on a particular kind of sensor, it may be adapted to any high-k, high-Q nc-AFM probe used under similar conditions, such as silicon cantilevers and LERs. Keywords: low temperature; non-contact atomic force microscopy; qPlus sensors; quartz tuning fork; stiffness calibration

Unveiling the nature of atomic defects in graphene on a metal surface

• Karl Rothe,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2024, 15, 416–425, doi:10.3762/bjnano.15.37

• ) topographies have been claimed to be in accordance with, for example, single-C vacancy sites. However, clear-cut evidence for a missing C atom in the graphene lattice has remained elusive. Therefore, in addition to an STM, an atomic force microscope (AFM) has been used in the present study to unveil the

• geometric structure of the defect sites. Surprisingly, the smallest defect in graphene on Ir(111), which appears as a depression in STM images and, therefore, may readily be assigned to a single-C vacancy site, gives rise to an undistorted graphene lattice in AFM images. In contrast, slightly larger defects

• of defects. Experimental A combined STM-AFM was operated in ultrahigh vacuum (5 × 10−9 Pa) and at low temperature (5 K). Surfaces of Ir(111) were cleaned by Ar+ ion bombardement and annealing. The epitaxial growth of graphene proceeded by exposing the heated (1300 K) Ir(111) surface to the gaseous

Investigating ripple pattern formation and damage profiles in Si and Ge induced by 100 keV Ar⁺ ion beam: a comparative study

• Indra Sulania,
• Harpreet Sondhi,
• Tanuj Kumar,
• Sunil Ojha,
• G R Umapathy,
• Ambuj Mishra,
• Ambuj Tripathi,
• Richa Krishna,
• Devesh Kumar Avasthi and
• Yogendra Kumar Mishra

Beilstein J. Nanotechnol. 2024, 15, 367–375, doi:10.3762/bjnano.15.33

• microscopy (AFM) [3] and transmission electron microscopy (TEM), it is possible to visualize these features. Formation of dots, ripples, and pits have been well studied using IBS [4][5][6][7][8][9]. In the last few decades, numerous efforts have been made to understand IBS through simulations [10] as well as

• loss values were found to be 47.75 and 59.61 eV/Å for Si and Ge, respectively. The range of Ar ions in Si is 106.5 nm and that in Ge is 72.2 nm. The pristine and irradiated samples were characterized by AFM (Nanoscope IIIa controller, Bruker, USA) using an RTESP tip with radius of curvature of ≈10 nm

• samples were studied via AFM for the surface topography and change in root-mean-square (RMS) surface roughness. Figure 1 shows AFM images of pristine and 100 keV Ar+ ion-irradiated Si samples. Pristine samples show a smooth surface with a surface roughness of ≈0.5 nm as observed in Figure 1A (a). Figure

Controllable physicochemical properties of WO_x thin films grown under glancing angle

• Rupam Mandal,
• Aparajita Mandal,
• Alapan Dutta,
• Rengasamy Sivakumar,
• Sanjeev Kumar Srivastava and
• Tapobrata Som

Beilstein J. Nanotechnol. 2024, 15, 350–359, doi:10.3762/bjnano.15.31

• −7 mbar). The thickness of the films was measured using a surface profilometer (Ambios, XP 200). The surface morphology of the as-deposited and the annealed films was acquired using tapping mode AFM (Asylum Research). AFM images were recorded at different places on each sample to confirm the film

• uniformity. WSxM software was used to carry out AFM image analysis. Kelvin probe force microscopy (KPFM) was used to study the local work function of the WOx films. WOx samples were removed from the high-vacuum environment right before the KPFM measurements to avoid any contamination in air. For KPFM

• electrons under the InLens configuration. The optical characteristics of the films were examined using a UV–Vis–NIR spectrophotometer (Shimadzu-3101PC) equipped with an unpolarised light source (300–1200 nm wavelength range). Results and Discussion Figure 1a–d depicts AFM topographic images of as-deposited

Determining by Raman spectroscopy the average thickness and N-layer-specific surface coverages of MoS₂ thin films with domains much smaller than the laser spot size

• Felipe Wasem Klein,
• Jean-Roch Huntzinger,
• Vincent Astié,
• Damien Voiry,
• Romain Parret,
• Houssine Makhlouf,
• Sandrine Juillaguet,
• Jean-Manuel Decams,
• Sylvie Contreras,
• Périne Landois,
• Ahmed-Azmi Zahab,
• Jean-Louis Sauvajol and
• Matthieu Paillet

Beilstein J. Nanotechnol. 2024, 15, 279–296, doi:10.3762/bjnano.15.26

• when using precise transfer or AFM tip manipulation techniques [20], twisted MoS2 can be formed with two adjacent layers stacked with a relative twist angle (θ) varying from 0 to 60°. Such twisted-layered MoS2 structures can exhibit a variety of interesting physical properties including unconventional

• mainly composed of 1L-MoS2 and suggesting that the proportions of 2L-MoS2, 3L-MoS2, or more gradually increase with , which is compatible with AFM observations (not shown). To get further insight on the number of layer distributions in DLI-PP-CVD samples, we have measured their ULF modes. Representative

• Nmax being the largest number of layers present in the sample, the definition of the average number of layers can be written as and the total coverage (including bare substrate areas) is obviously 100%: AFM imaging (see Supporting Information File 1, Figure S4) reveals that for > 1.25, the surface is

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

• , gravitational waves acting on a 40 kg mirror in LIGO [3], or atomic-scale tip–surface forces acting on a 40 pg cantilever in an atomic force microscope (AFM). For AFM cantilevers operating at room temperature close to their fundamental resonant frequency in the kilohertz-to-megahertz range, optical

• point where motion detection becomes the limiting source of noise. In this context, the principles of cavity optomechanics may improve the sensitivity of AFM force sensors. Cryogenic AFM further enables the use of superconducting microwave resonators in a cavity optomechanical detection scheme [4][5][6

• equilibrium. With AFM, this is typically done by optoelectronic means, using either interferometry [9][10][11] or beam deflection [12][13][14]. These optical methods often require delicate in situ alignment of the detector to the mechanical force transducer. An integrated detector requiring no alignment is

Quantitative wear evaluation of tips based on sharp structures

• Ke Xu and
• Houwen Leng

Beilstein J. Nanotechnol. 2024, 15, 230–241, doi:10.3762/bjnano.15.22

• Ke Xu Houwen Leng School of Electrical & Control Engineering, Shenyang Jianzhu University, Shenyang 110168, China 10.3762/bjnano.15.22 Abstract To comprehensively study the influence of atomic force microscopy (AFM) scanning parameters on tip wear, a tip wear assessment method based on sharp

• structures is proposed. This research explored the wear of AFM tips during tapping mode and examined the effects of scanning parameters on estimated tip diameter and surface roughness. The experiment results show that the non-destructive method for measuring tip morphology is highly repeatable. Additionally

• , a set of principles for optimizing scanning parameters has been proposed. These principles consider both scanning precision and tip wear. To achieve these results, an AFM probe was used to scan sharp structures, precisely acquiring the tip morphology. Tip wear was minimized by employing lower

Ion beam processing of DNA origami nanostructures

• Leo Sala,
• Agnes Zerolová,
• Violaine Vizcaino,
• Alain Mery,
• Alicja Domaracka,
• Hermann Rothard,
• Philippe Boduch,
• Dominik Pinkas and
• Jaroslav Kocišek

Beilstein J. Nanotechnol. 2024, 15, 207–214, doi:10.3762/bjnano.15.20

• by ion beams, modeling ion implantation, lithography, and sputtering conditions. Structural changes in 2D DNA origami nanostructures deposited on Si are analyzed using AFM imaging. The observed effects on DNA origami include structure height decrease or increase upon fast heavy ion irradiation in

• . Preparation of dry samples and AFM imaging Silicon wafers were cut into ∼7 × 7 mm2 chips and were then plasma-cleaned in air using a Roplass RPS40+ plasma cleaner, which generates a thin layer of plasma by diffuse coplanar surface barrier discharge [35]. The Si surface is exposed to the thin plasma layer for

• , we only evaluated samples on Si. AFM imaging was used to check and subsequently analyze the irradiated samples. The imaging was performed in air using a Dimension Icon AFM (Bruker) in ScanAsyst mode which employs PeakForce Tapping Technology and ScanAsyst probes (40 kHz, 0.4 N/m). Image processing

Graphene removal by water-assisted focused electron-beam-induced etching – unveiling the dose and dwell time impact on the etch profile and topographical changes in SiO₂ substrates

• Aleksandra Szkudlarek,
• Jan M. Michalik,
• Inés Serrano-Esparza,
• Zdeněk Nováček,
• Veronika Novotná,
• Piotr Ozga,
• Czesław Kapusta and
• José María De Teresa

Beilstein J. Nanotechnol. 2024, 15, 190–198, doi:10.3762/bjnano.15.18

• provides information about the degree of damage caused by this method. Atomic force microscopy (AFM) measurements reveal important aspects of topographical changes induced in the substrate and help to establish optimized conditions for the etching process. Results The fundamentals of water-assisted FEBIE

• studies: A) optical microscopy, B) scanning electron microscopy (SEM), C) AFM, and D) correlative probe and electron microscopy (CPEM). The optical contrast of graphene placed onto SiO2/Si allows us to easily distinguish between its mono-, bi-, triple, and thicker flakes layers. The values (approx. 2.5 nm

• for a monolayer of graphene onto SiO2) measured using AFM, shown in the insets of Figure 1D, agree with the data obtained in studies presenting femtosecond laser thinning of graphene [28]. In addition to the region located below the baseline, we also observe an elevation in the central part of the

CdSe/ZnS quantum dots as a booster in the active layer of distributed ternary organic photovoltaics

• Gabriela Lewińska,
• Piotr Jeleń,
• Zofia Kucia,
• Maciej Sitarz,
• Łukasz Walczak,
• Bartłomiej Szafraniak,
• Jerzy Sanetra and
• Konstanty W. Marszalek

Beilstein J. Nanotechnol. 2024, 15, 144–156, doi:10.3762/bjnano.15.14

• carried out for three incidence angles (65°, 70°, and 75°). A Bruker atomic force microscope (AFM) MULTIMODE 8 was used in the measurements in the ScanAsyst in Air mode, using silicon nitride probes (with a nominal tip radius of 2 nm and a spring constant equal to 0.4 N/m). The substrate was

• , which favored the charging process of the metallic electrode. These were used to facilitate the transport of charge carriers between the electrode and the layer, which can become problematic because of limitations in the conductivity of organic materials. The changes in roughness presented from the AFM

• coefficients of quantum dots+P3HT+PC71BM mixtures. AFM 2D images of quantum dots+P3HT+PCBM mixtures. Raman plots of P3HT, PCBM, and QDs+P3HT+PCBM mixtures. (a, b) UPS survey spectra, (c) comparison of the cutoffs, and (d) comparison of the UPS spectra of the valence bands. Energy diagram for potential ternary

Enhanced feedback performance in off-resonance AFM modes through pulse train sampling

• Mustafa Kangül,
• Navid Asmari,
• Santiago H. Andany,
• Marcos Penedo and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2024, 15, 134–143, doi:10.3762/bjnano.15.13

• Mustafa Kangul Navid Asmari Santiago H. Andany Marcos Penedo Georg E. Fantner Laboratory for Bio- and Nano-Instrumentation, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne CH-1015, Switzerland 10.3762/bjnano.15.13 Abstract Dynamic atomic force microscopy (AFM) modes that operate

• rate and therefore enables higher scan rates while refining the mechanical property mapping. Keywords: atomic force microscopy (AFM); feedback control; off-resonance tapping (ORT); pulsed-force mode; Introduction Constant force mode, a widely used AFM imaging mode, utilizes a feedback controller that

• reads the deflection of the cantilever and keeps the applied tip–sample vertical force at a fixed setpoint value by adjusting the voltage applied to a Z axis nano-positioner. While this AFM mode achieves high precision in controlling vertical forces, the high lateral forces applied while scanning limits

unDrift: A versatile software for fast offline SPM image drift correction

• Tobias Dickbreder,
• Franziska Sabath,
• Lukas Höltkemeier,
• Ralf Bechstein and
• Angelika Kühnle

Beilstein J. Nanotechnol. 2023, 14, 1225–1237, doi:10.3762/bjnano.14.101

• conditions For the above presentation of the working principle of our software, we used AFM images with good atomic contrast and reasonable drift velocities. In experiments, however, it is not always possible to reach these desirable conditions, which is why we want to show that our software can also deal

• velocity. In Figure 4a,b, we show two consecutive AFM images of a calcium fluoride (111) surface recorded under ultrahigh vacuum conditions. The periodic structures observed in these two raw-data images (see red unit cells in Figure 4a,b) show a striking difference compared to each other and compared to

• part of the second image for drift correction. This conclusion is confirmed by the derived unit cell dimensions of 5.1 × 10−10 m × 8.2 × 10−10 m with an angle of 89.8°, which fit the expected values (4.99 × 10−10 m × 8.10 × 10−10 m, 90.0°; [50]) within the experimental accuracy of our AFM instrument

Determination of the radii of coated and uncoated silicon AFM sharp tips using a height calibration standard grating and a nonlinear regression function

• Perawat Boonpuek and
• Jonathan R. Felts

Beilstein J. Nanotechnol. 2023, 14, 1200–1207, doi:10.3762/bjnano.14.99

• of Engineering, Texas A&M University, College Station, Texas, 77843, USA 10.3762/bjnano.14.99 Abstract AFM sharp tips are used to characterize nanostructures and quantify the mechanical properties of the materials in several areas of research. The analytical results can show unpredicted errors if we

• do not know the exact values of the AFM tip radius. There are many techniques of in situ measurements for determining the actual AFM tip radius, but they are limited to uncoated tips. This paper presents an alternative and simple method to determine the radii of coated tips and an uncoated tip. Pt

• -coated, Cr/Au-coated, and uncoated Si tips were used to scan a calibration standard grating in AFM contact mode with sub-nanonewton load to obtain the curved scan profile of the edge corner of the grating structure. The data points of the curved profile of each tip were fitted with a nonlinear regression

A combined gas-phase dissociative ionization, dissociative electron attachment and deposition study on the potential FEBID precursor [Au(CH₃)₂Cl]₂

• Elif Bilgilisoy,
• Ali Kamali,
• Thomas Xaver Gentner,
• Gerd Ballmann,
• Sjoerd Harder,
• Hans-Peter Steinrück,
• Hubertus Marbach and
• Oddur Ingólfsson

Beilstein J. Nanotechnol. 2023, 14, 1178–1199, doi:10.3762/bjnano.14.98

• three experiments. The FEBID structures were investigated by SEM and noncontact atomic force microscopy (AFM). Figure 3a shows the SEM images of the deposits along with the respective deposition parameters. Magnified sections from these SEM images are shown in Figure 3b. Auger electron spectroscopy was

• 10.1 nm, respectively). At 3 nA, on the other hand, a clear size reduction to 8.2 nm is observed in the SEM images. This size reduction with increasing deposition current is even clearer from the AFM images as discussed in the following section. From the AES data shown in Figure 3c, the atomic

• purification of FEBID deposits, where carbon removal led to ≈18% height reduction of the respective nanoparticles [42]. Notwithstanding, changes in the deposition time and in the associated different volume of the deposited material may also contribute to the observed particle size reduction. AFM of FEBID on

Spatial variations of conductivity of self-assembled monolayers of dodecanethiol on Au/mica and Au/Si substrates

• Julian Skolaut,
• Jędrzej Tepper,
• Federica Galli,
• Wulf Wulfhekel and
• Jan M. van Ruitenbeek

Beilstein J. Nanotechnol. 2023, 14, 1169–1177, doi:10.3762/bjnano.14.97

• applied method uses conductive atomic force microscopy (CAFM). In this technique, a conductive probe is used in an AFM, which allows for imaging the surface topography (and other characteristics such as adhesion and stiffness) with lateral resolution while simultaneously being able to measure current

• DDT/ethanol solution and heated to ≈80 °C for 1 h. After gradual cooldown, the samples were again rinsed and dried in N2 atmosphere in the glovebox. The obtained samples were studied using a commercially available JPK NanoWizard® 3 AFM setup. The setup has been upgraded by a CAFM tip holder with an

Hierarchically patterned polyurethane microgrooves featuring nanopillars or nanoholes for neurite elongation and alignment

• Lester Uy Vinzons,
• Guo-Chung Dong and
• Shu-Ping Lin

Beilstein J. Nanotechnol. 2023, 14, 1157–1168, doi:10.3762/bjnano.14.96

• uncrosslinked PDMS monomers (Supporting Information File 1, Figure S3C). Atomic force microscopy (AFM) scans of the samples (Figure 1F–H) show that the nanopillars and nanoholes have sub-micrometer feature sizes and a periodicity of around 1.2 µm. Due to AFM measurement artifacts, especially for lateral

• PU solvent casting (Figure 3B), the hierarchical patterns were successfully replicated on PU films (Figure 3C–E and Supporting Information File 1, Figure S12). As can be seen from the AFM scans (Figure 3F–H), the microridge areas were around 15 µm in width, while the microgroove areas were slightly

• carefully peeled off from the molds and cut to form the final samples (Figure 1B(iv) and 3B(iv)). The PU substrates were characterized using SEM, AFM, and water CA measurements, as described in detail in Supporting Information File 1. PC12 culture and neurite outgrowth experiment PC12 cells (ATCC CRL-1721

Elasticity, an often-overseen parameter in the development of nanoscale drug delivery systems

• Agnes-Valencia Weiss and
• Marc Schneider

Beilstein J. Nanotechnol. 2023, 14, 1149–1156, doi:10.3762/bjnano.14.95

• determine mechanical properties of nanoparticles (or their corresponding bulk materials) highlighting quartz crystal microbalance, rheology, and atomic force microscopy (AFM) are summarized by Li et al. [18]. Another often reported method is particle deformability, being extrusion a possibility for

• nanoparticles [13] and microfluidic setups for particles that are large enough to be imaged by light microscopy techniques [19]. As AFM is currently the only technology capable to measure mechanical properties of single nanoparticles, we will concentrate on this technique. Atomic force microscopy currently

• . However, more complete approaches can be applied [24], which consider the situation of a given system. An example is the Johnson–Kendall–Roberts (JKR) theory, including surface forces, the influence on the adhesion, deformation, and contact behavior between the nanoparticle and the AFM probe suitable for

A multi-resistance wide-range calibration sample for conductive probe atomic force microscopy measurements

• François Piquemal,
• Khaled Kaja,
• Pascal Chrétien,
• José Morán-Meza,
• Frédéric Houzé,
• Christian Ulysse and
• Abdelmounaim Harouri

Beilstein J. Nanotechnol. 2023, 14, 1141–1148, doi:10.3762/bjnano.14.94

• work, we demonstrate the development of a multi-resistance reference sample for calibrating resistance measurements in conductive probe atomic force microscopy (C-AFM) covering the range from 100 Ω to 100 GΩ. We present a comprehensive protocol for in situ calibration of the whole measurement circuit

• encompassing the tip, the current sensing device, and the system controller. Furthermore, we show that our developed resistance reference enables the calibration of C-AFM with a combined relative uncertainty (given at one standard deviation) lower than 2.5% over an extended range from 10 kΩ to 100 GΩ and lower

• than 1% for a reduced range from 1 MΩ to 50 GΩ. Our findings break through the long-standing bottleneck in C-AFM measurements, providing a universal means for adopting calibrated resistance measurements at the nanoscale in the industrial and academic research and development sectors. Keywords