SPM workshop 2015 seminář o metodách blízkého pole Lednice 25.3. – 27.3.2015 Main sponsor: Sponsors: Wednesday 25.3. 14:00 – 14:10 14:10 – 14:55 Miklós Kellermayer . . . . . . . . . . . . . . . . . 14:55 – 15:15 Tímea Feller . . . . . . . . 15:15 – 15:35 Tamás Bozó . . . . . . . . . 15:35 – 15:55 Petr Skládal . . . . . . . . 15:55 – 16:15 Martin Munzar . . . . . 16:15 – 16:35 16:35 – 16:55 Róbert Nagy . . . . . . . . 16:55 – 17:15 Lukáš Fojt . . . . . . . . . . 17:15 – 17:35 Egor Ukraintsev . . . . . 17:35 – 17:55 Anton Manakhov . . . 17:55 – 18:15 Dušan Novotný . . . . . 19:00 – 20:00 Opening Expanding the spatial, temporal and mechanical scales of biomolecular scanning force microscopy Fibrin formation and degradation followed with AFM-based nano-thrombelastography Morphological and nanomechanical characterization of cochleate particles AFM for characterization of biomolecules, affinity complexes and cells RMI (NT-MDT) company presentation Coffee break Highly oriented-, epitaxially generated amyloid nanoarray for nanobiotechnological applications In-situ study of magnesium alloys degradation in SBF solutions using AFM Impact of gamma radiation on biomolecules studied by atomic force microscopy The behaviour of amine-rich layers in water studied by AFM MT-M company presentation Dinner Thursday 26.3. 9:00 – 9:45 Pavel Jelínek . . . . . . What we can learn from high-resolution AFM/STM images: experiment and theory 9:45 – 10:05 Anna Charvátová Study of uncertainty measurement of monoatomic step on Campbell . . . . . . . . . . . Si 7 × 7 using DFT 10:05 – 10:25 Jan Berger . . . . . . . . . . Force Driven Single-Atom Manipulation on a Low-Reactive Si Surface for Tip Sharpening 10:25 – 10:45 Mykola Telychko . . . . Quantum interference on doped graphene/SiC systems 10:45 – 11:05 Coffee break 11:05 – 11:50 Alexander Riss . . . Single-molecule reactions – Imaging chemical bonds and tuning electronic structure 11:50 – 12:10 Štefan Lányi . . . . . . . . Scanning Charge-Transient Spectroscopy 12:10 – 12:30 Tomáš Samuely . . . . . Dynamic visualization of periodic motion of nanoobjects 12:30 – 14:00 Lunch 14:00 – 14:20 Zdeňka Hájková . . . . . Local conductivity measurements of CVD graphene transparent electrode for thin film silicon solar cells 14:20 – 14:40 Dušan Novotný . . . . . MT-M company presentation 14:40 – 15:00 Matěj Hývl . . . . . . . . . Correlative microscopy on radial junction solar cells based on silicon nanowires 15:00 – 15:20 Jan Čermák . . . . . . . . . Correlated SPM characterizations of CVD graphene on copper and cuprous oxide 15:20 – 15:40 Filip Münz . . . . . . . . . . Organic semiconductors in self-organized layers 15:40 – 16:00 Jan Vávra . . . . . . . . . . . 16:00 – 16:20 16:20 – 17:05 Deb Roy . . . . . . . . . . . 17:05 – 17:25 Marek Černík . . . . . . . 17:25 – 17:45 Petr Klapetek . . . . . . . 17:45 – 18:05 Daniel Haško . . . . . . . . 18:05 – 18:25 Dušan Novotný . . . . . 19:30 – 23:00 High-Resolution and High-Speed Atomic Force Microscopy Simultaneous to Advanced Optical Microscopy Coffee break Nano-optics for Nano-chemistry and Nanostructures Correlating 3D Raman Imaging with Scanning Microscopy Techniques FDTD modeling for localised Raman measurements The combination of scanning probe and optical interferometric microscopic methods for characterization of materials and components for FIC. MT-M company presentation Social evening Friday 27.3. 9:30 – 10:15 P.-Olivier Chapuis 10:15 – 10:35 Jan Vaniš . . . . . . . . . . . 10:35 – 10:55 Jan Martinek . . . . . . . 10:55 – 11:15 11:15 – 11:35 Vilma Buršíková . . . . 11:35 – 11:55 Ondřej Číp . . . . . . . . . . 11:55 – 12:15 Vlastimil Píč . . . . . . . . 12:15 – 12:35 Josef Lazar . . . . . . . . . . 12:35 – 12:55 Michal Urbánek . . . . . 13:00 Scanning thermal microscopy: micro to nanoscale thermal properties Scanning thermal microscopy of thin PLD layers Topography artifacts compensation in scanning thermal microscopy on rough surfaces Coffee break Quantitative mapping of mechanical properties using quasistatic and dynamic nanoindentation and AFM techniques Scale linearity testing of a laser interferometer of metrological AFM with the optical frequency comb Educational Macromodel of AFM Interferometric coordinate position sensing with semiconductor laser sources AFM characterization of structures prepared by e-beam: on the border between micro and nano End of the workshop, lunch Wed 14:10 – 14:55 Miklós Kellermayer kellermayer.miklos@med.semmelweis-univ.hu Semmelweis University Tűzoltó str. 37-47., Budapest, H1094 Hungary Expanding the spatial, temporal and mechanical scales of biomolecular scanning force microscopy The scanning force microscope (SFM) has become an indispensible tool in the investigation of the global and local structure, dynamics, nanomechanics and interactions of biomolecular systems. However, the method is often impeded by limitations of its spatial, temporal or mechanical resolution. We have in the recent past directed effort towards expanding these resolution scales and adapting them on specific biological molecules and self-assembled, supramolecular systems such as cytoskeletal filaments, amyloid fibrils, motor proteins, lipids and nucleic acids. To simultaneously exploit the advantages of SFM and fluorescence, we developed a spatially and temporally synchronized total internal reflection fluorescence and atomic force microscope system. Using the technique correlated sample topography and fluorescence images can be recorded, soft biomolecular systems can be mechanically manipulated in a targeted fashion, and the fluorescence of mechanically stretched molecules can be followed with high temporal resolution. To enhance the temporal resolution of SFM for the purpose of following fast biomolecular events, we applied a simply modified technique called scanning force kymography. Using the method we monitored the epitaxially-driven growth, on mica surface, of individual amyloid fibrils with near-subunit (∼1 nm) spatial and millisecond temporal resolution. The employed scanning force kymography method may be adapted to analyze the assembly dynamics of a wide range of linear biopolymers. Finally, to expand the nanomechanical scale and correlate it with specific structural information, we combined SFM with meniscus-force-based biomolecular manipulation. By using this method we are able to detect the structural consequences of mechanically-driven protein domain unfolding, thereby paving the way towards understanding the role of nanomechanics in the structure and function of biomolecules. Wed 14:55 – 15:15 Tímea Feller timea.feller@gmail.com Semmelweis University Hungary, Budapest (1085) Üllői út 26. Tímea Feller, Miklós S.Z. Kellermayer and Balázs Kiss Fibrin formation and degradation followed with AFM-based nano-thrombelastography Blood clots or thrombi normally form at the site of vascular injury to stop bleeding, but can also appear at undesired locations occluding blood vessels, thus causing heart attack or stroke. The scaffold of the thrombus is a three-dimensional fibrin network, which, though constituting only 0.25% of the clot, is the main determinant of the mechanical properties. We investigated nanoscale changes in the viscoelasticity of the 3D-fibrin network during fibrin formation and enzyme-induced fibrinolysis by using a novel, atomicforce-microscope (AFM)-based application of force spectroscopy, named nano-thrombelastography. Clot formation was initiated by adding Ca2+ to fresh, anti-coagulated mixed human plasma droplet on a glass surface. For measuring the nanoscale elastic and viscous properties of the fibrin network, the cantilever of the AFM was immersed completely into the plasma droplet without making contact with the substrate surface, and moved vertically with a constant rate. The cantilever bending was correlated with the mechanical properties of the fibrin-clot: maximal force difference referred to elasticity and the area of hysteresis loop referred to viscosity. Whereas the global features of the time-dependent change in cantilever deflection corresponded well to a macroscopic thrombelastogram, the underlying force spectra revealed large, sampledependent oscillations in the range of 3-50 nN. Upon enzyme treatment the nano-thrombelastogram signal decayed gradually. The decay was driven by a decrease in thrombus elasticity, whereas thrombus viscosity decayed with a time delay. Morphological changes were followed by AFM scanning on polymerized fibrin. 4 Mature fibrin appeared with a surface roughness of 23.7 nm discrete steps that correspond well to the length of a fibrinogen monomer. Enzyme treatment resulted in the decrease of filament height and width, while the average of surface roughness remained 23.7 nm. Thus, the initial decay of thrombus elasticity during fibrinolysis may be caused by the axial rupture of fibrin fibers. In summary, the nano-thrombelastographic method developed herein allows us to reveal the microscopic detail of the structural and dynamical changes associated with blood clotting. Wed 15:15 – 15:35 Tamás Bozó bozo.tamas@med.semmelweis-univ.hu Semmelweis University, Department of Biophysics and Radiation Biology Tuzolto str. 37-47., 1094, Budapest, Hungary Tamás Bozó, Richárd Brecska, Pál Gróf, Miklós S. Z. Kellermayer Morphological and nanomechanical characterization of cochleate particles Cochleates are nanoscale rolls of negatively-charged phospholipid membranes held together by calcium which may be used as biocompatible drug delivery vehicles. Atomic force microscopy and force spectroscopy were utilized to reveal the topographical structure and hitherto unknown nanomechanical properties of individual cochleate nanoparticles. Manipulation of individual cochleate nanoparticles revealed unexpected levels of stiffness and membrane-rupture forces of 4.2-12.5 N/m and 45.3-278 nN, respectively, which are an order of magnitude greater than those of tough viral nanoshells. The high resilience of cochleates indicates that cross-linking lipid membrane films provides stability large enough for mechanical protection of encapsulated materials such as proteins, pharmaceuticals or even the axon of myelinated neurons. Wed 15:35 – 15:55 Petr Skládal skladal@chemi.muni.cz CEITEC, Masarykova univerzita Kamenice 5, 625 00 Brno P. Skládal, J. Přibyl, V. Horňáková, M. Pešl, P. Bouchal, P. Gereg, M. Jakubec, Z. Farka, D. Kovář AFM for characterization of biomolecules, affinity complexes and cells The instrumentation and services available at the Core Facility of Nanobiotechnology, CEITEC Masaryk University, will be introduced. The research possibilities will be demonstrated on experiments with proteins, nucleic acids and their affinity complexes - interaction of ssDNA binding protein with oligonucleotides and immunoreaction between antibody and antigen. Properties of cellular membrane will be characterised in relation to the changes accompanying malignant transformation. Simultaneous recording of contractions and electric activity of cardiomyocytes will be presented using AFM cantilever with conductive tip functioning as nanomechanical transducer for cellular biosensor suitable for evaluation of fyziologically active compounds in real time. Wed 15:55 – 16:15 Martin Munzar RMI (NT-MDT) company presentation 5 Wed 16:35 – 16:55 Róbert Nagy robert.n.86@gmail.com Semmelweis University - Department of Biophysics and Radiation Biology Tűzoltó u. 37-47., Budapest, Distr. IX., H-1094 Nagy R., Hársfalvi V., Murvai Ü., Fülöp L., Penke B and Kellermayer MSZ Highly oriented-, epitaxially generated amyloid nanoarray for nanobiotechnological applications The self-assembly properties of biomolecular systems are of fundamental appeal for nanobiotechnological applications. However, the lack of easy chemical access and nano- to micro-scale structural order often hinders the nanotechnological use of conventional biomolecules. We have previously shown that Aβ25-35 forms a trigonally oriented network on mica by epitaxial growth mechanisms. Furthermore, a mutant form of the peptide, Aβ25-34_N27C, in which the Cys27 is in principle chemically accessible, also forms an oriented network on mica. In the present work we explored whether the oriented amyloid-fibril network can be functionalized via sulfhydryl chemistry and whether it may for the basis of constructing more complex and advanced structures. Oriented network of amyloid fibrils was generated by incubating mutant, Aβ25-34_N27C peptides or mixtures of the mutant and wild-type peptides on mica in the presence of varying KCl concentration in order to fine tune the network’s structural properties. To functionalize the fibrils we used maleimido-nanogold (1.4 nm). The structure of the functionalized network was investigated with AFM. We were able to tune the average length of the amyloid fibrils by adjusting the peptide and KCl concentration in the buffer solution. In the nanogold-labeled amyloid network spherical particles of 1.4 nm diameter lined up along the oriented fibrils, demonstrating that the fibrils can indeed be chemically addressed and functionalized. Thus, the oriented amyloid network may be used towards the construction of functional biomolecular nanoarrays with complex, tunable geometries and properties. Finally, the amyloid network developed herein may lend itself to sophisticated applications in which its electronic topology carries additional, highly differentiated functionalities. Wed 16:55 – 17:15 Lukáš Fojt fojt@ibp.cz Biofyzikální Ústav Av Čr, V.v.i. Královopolská 2590/135, 612 00 Brno Lukáš Fojt, Pavel Doležal In-situ study of magnesium alloys degradation in SBF solutions using AFM Magnesium and magnesium alloys based materials find, due to their specific properties, huge application possibilities mainly in automotive, engineering, transport and space industry. Their usage for biomedical engineering applications such as biodegradable tissue and cardiovascular implants is also an important field of application. Important properties of magnesium alloys are biocompatibility and/or biodegradability, high specific strength and high internal dumping values. Main fields of magnesium alloys study, in the last decade, are development of new biodegradable alloys, investigation of new production and processing technologies and evaluation of magnesium alloys electrochemical and degradation properties in SBF solutions. From the point of view of interaction of magnesium alloys with biological systems, cytotoxicity, viability and biodegradability based experimental in vitro tests were proposed. Magnesium alloys degradation is strongly dependent on their chemical composition and production and processing of the alloy, which influence the reached microstructure, chemical and phase composition of the material. Corrosion mechanisms studies and analysis performed on magnesium alloys are nowadays focused on degradation analysis in SBF solutions. Within the cooperation of the Institute of Biophysics AS CR, v. v. i. and the Faculty of Mechanical Engineering BUT new methodology for in-situ evaluation of selected magnesium alloys degradation in SFB solutions by Atomic force microscopy (AFM) was developed and proposed. Veeco Multimode VIII AFM was used for the studies performed in water cell by continual SBF solution 6 exchange. Selected magnesium alloys degradation was examined in chemically different corrosion solutions (different SBF - Hanks solutions), simulated body fluids. AZ31 and AZ61 magnesium alloy processed by advanced squeeze casting method were used for initial experiments. Degradation properties of examined alloys were influenced by different microstructure, chemical and phase composition. In-situ methodology developed and proposed for magnesium alloys degradation evaluation by AFM contributed in a significant way to understanding of magnesium alloys degradation mechanism and rate. From the methodology point of view, exist a strong expectation of developed in-situ tests. Wed 17:15 – 17:35 Egor Ukraintsev ukraints@fzu.cz Fyzikální ústav AV ČR Cukrovarnická 10, Praha 6 E. Ukraintsev, J. Vachelová, M. Davídková, A. Kromka, B. Rezek Impact of gamma radiation on biomolecules studied by atomic force microscopy The AFM measurements, performed in native environment, can reveal conformation of adsorbed molecules on different substrates. In the PeakForce Nanomechanical Mapping mode (PFQNM) the approachretraction force curves are collected and evaluated in every image point. Available signals are topography, adhesion, stiffness, dissipation and deformation. We used PFQNM to investigate the impact of gamma radiation on fetal bovine serum (FBS) adsorbed on hydrogen- and oxygen-terminated monocrystalline diamonds (MCD). Gamma radiation (5-300 Gy) caused increasing aggregation of protein molecules. The impact of gamma radiation was higher for FBS adsorbed on H-MCD compared to O-MCD, which may be related with different protein-substrate interaction. Wed 17:35 – 17:55 Anton Manakhov manakhov@mail.muni.cz Plasma Technologies, Central European Institute of Technology – Masaryk University 61137 Brno, Kotlářská 2 Anton Manakhov, David Nečas, Lenka Zajíčková The behaviour of amine-rich layers in water studied by AFM Amine-rich plasma polymer layers have large potential for many biomedical applications such as tissue engineering, would dressing or biosensing thanks to their high reactivity and positive surface charge. However, the stability of such layers in water, which is critical for the biomedecal use, is often very low. In this work we studied the water stability of amine-rich plasma layers prepared on silicon wafers by low pressure plasma polymerization of cyclopropylamine (CPA). The chemical composition of the layers was studied by Fourier Trasform IR and X-ray Photoelectron Spectroscopies, whereas Atomic Force Microscopy was used for the evaluation of the surface topography. During this study curious morphological changes were observed on a subset of the films after immersion in water. The layer buckling led to the formation of perfect ring-shaped structures on the film surface. Interestingly, the cracking occurred only inside the layer and not at the interface with the substrate, i.e. only the top part of the film was cracked. We will present a study of the ring geometrical properties measured by AFM in dependence of the film deposition conditions. Wed 17:55 – 18:15 Dušan Novotný MT-M company presentation 7 Thu 9:00 – 9:45 Pavel Jelínek jelinekp@fzu.cz Fyzikální ústav AV ČR, v. v. i. Cukrovarnická 10, Prague 6 What we can learn from high-resolution AFM/STM images: experiment and theory The recent progress in Atomic Force Microscopy (AFM) and Scanning Tunneling Microscopy (STM) using functionalized tips provided unprecedented atomic resolution of single organic molecules [1, 2]. However, the origin of the high-resolution AFM/STM imaging contrast is still not well understood. Here we will present 3D maps of the force, tunneling current and dissipation over a monolayer of PTCDA molecules deposited on Ag(111) acquired at 1.2 Kelvin with Xe-functionalized tip (see Fig. 1.). We will compare detailed contrast features of the force maps at various tip-sample separations to a numerical model [3, 4]. The numerical model describes relaxation of the functionalized tip due to Pauli repulsion and the electrostatic interaction with surface. Combing the experimental and theoretical evidence, we will explain the high-resolution imaging mechanism [3], artifacts [3, 5] and a possibility to map out intra-molecular charge distribution in real-space [4]. We will also discuss a possibility to use experimental measurements to benchmark existing classical interatomic potentials (force fields) and devise new forms of the potentials. Fig.1. High resolution AFM/STM images of PTCDA molecules deposited on Ag(111) surface acquired with Xe-functionalized tip at different tip sample distances. [1] [2] [3] [4] [5] L. Gross et al., Science 325,1110 (2009). C. Weiss et al., Phys.Rev.Lett. 105, 086103 (2010). P. Hapala et al., Phys. Rev. B 90, 085421 (2014). P. Hapala et al., Phys. Rev. Lett. 113, 226101 (2014). J. Zhang et al., Science 342, 611 (2013). Thu 9:45 – 10:05 Anna Charvátová Campbell acampbellova@cmi.cz Český metrologický institut Okružní 31, 638 00 Brno Anna Charvátová Campbell, Pavel Jelínek, Petr Klapetek Study of uncertainty measurement of monoatomic step on Si 7 × 7 using DFT Monoatomic steps are very common means for calibration of atomic force microscopes. The interaction between the tip and the sample is studied using a density field theory. 8 Thu 10:05 – 10:25 Jan Berger bergerj@fzu.cz Fyzikální ústav AV ČR Cukrovarnická 10, Praha 6, 16200 Jan Berger, Evan J. Spadafora, Pingo Mutombo, Pavel Jelínek, Martin Švec Force Driven Single-Atom Manipulation on a Low-Reactive Si Surface for Tip Sharpening √ √ We investigated single atomic manipulation on the delta-doped B : Si(111) − 3 × 3R30◦ surface using a low temperature dynamic atomic force microscopy based on the Kolibri sensor. Through a controlled vertical displacement of the probe, we removed a single Si adatom in order to open a vacancy. We show that this process is completely reversible, by accurately placing a Si atom back into the vacancy site. In addition, we carried out DFT simulations to understand the underlying mechanism of the atomic manipulation in detail. This process also rearranges the atoms at the tip apex, which can be effectively sharpened in this way. Such sharper tips allow for a deeper look into the Si adatom vacancy site. Namely, we achieved high-resolution images of the vacancy showing subsurface Si dangling bond (DB) triplets, which surround the substitutional B dopant atom in the first bilayer. Thu 10:25 – 10:45 Mykola Telychko telychkom@gmail.com Institute of Physics of the AS CR Cukrovarnická 10 Prague 6 CZ-162 00 Mykola Telychko, Pablo Merino, Pingo Mutombo, Martin Ondráček, Prokop Hapala, Oleksandr Stetsovych, Pavel Jelínek, Martin Švec Quantum interference on doped graphene/SiC systems We report methodology for co-doping of epitaxial graphene grown on the SiC(0001) substrate by boron and nitrogen atoms. Nitrogen doping was achieved using direct nitrogen ion implantation into the graphene lattice and subsequent thermal stabilization. Boron doping was achieved by introducing the additional source of boron atoms during growth process of the graphene/SiC(0001). Atomically-resolved low-temperature STM/AFM measurements of well-defined single substitutional nitrogen and boron dopants reveal that the nitrogen dopants in graphene lattice feature a strong quantum interference effect, tunable by changing the tip-sample separation. The current dependence on the tip position is successfully modelled by DFT and STM simulations for the both types of dopants. [1] M. Telychko, et al, ACS Nano, 8(7):7318–7324, 2014. Thu 11:05 – 11:50 Alexander Riss alex@riss.at Institute of Applied Physics, Vienna University of Technology Wiedner Hauptstrasse 8-10/134, 1040 Wien, Austria Single-molecule reactions – Imaging chemical bonds and tuning electronic structure Organic molecules provide a versatile, abundant, and cost-effective platform for the development of functional materials in many technologically relevant fields, such as electronics and photovoltaics. Effective utilization of molecular systems relies on control of structure, arrangement and bonding between molecular units, as well as an understanding on how these parameters affect the physical and chemical properties of the material. Our studies focus on atomic-level investigations of surface-supported intra- and intermolecular reactions of organic molecules along with changes of their electronic properties. In particular, we resolved the bond rearrangements associated with cyclization reactions of single enediyne molecules by imaging the precise chemical structure of reactants and products (Fig. 1a), as well as intermediate species, using non-contact atomic force microscopy (nc-AFM). We used scanning tunneling microscopy and spectroscopy (STM/STS) 9 to study the formation of low-energy extended electronic states in conjugated polymer chains, which were synthesized by radical polymerization reactions on metal surfaces (Fig. 1b). Additionally, we show how backgated graphene devices can be used to change the alignment of the electronic levels of organic molecules thus opening up the possibility to control their chemical and physical properties. Figure 1: (a) Nc-AFM measurements showing the chemical structures of reactants and products of competitive pathways of an enediyne cyclization reaction on Ag(100). (b) Three-dimensional representation of a simultaneous nc-AFM and STM measurement of an individual conjugated polymer chain on Au(111). The nc-AFM measurement reflects the chemical structure of the 4-nm-long polymer (shown in white). In contrast. the STM measurement is sensitive to the electronic local density of states of the polymer’s lowest unoccupied molecular orbital (shown in blue-red-yellow). Thu 11:50 – 12:10 Štefan Lányi lanyi@savba.sk Fyzikálny ústav SAV Dúbravská cesta 9, Bratislava Scanning Charge-Transient Spectroscopy Charge-Transient Spectroscopy applied to materials on the nanoscale may offer interesting information not accessable by other means. We present results obtained with our microscope that is able to produce besides of the topography also local charge-transient data. We shall present results obtained on various materials like P3HT, grapheneoxide and graphene. Thu 12:10 – 12:30 Tomáš Samuely tomas.samuely@upjs.sk Centre of Low Temperature Physics, Institute of Physics, Faculty of Science, P. J. Šafárik University Park Angelinum 9, 04001 Košice, Slovakia Tomas Samuely, Matias Timmermans, Bart Raes, Joris van de Vondel, Victor V. Moshchalkov Dynamic visualization of periodic motion of nanoobjects Scanning probe microscopy offers unparalleled spatial resolution, but its poor temporal resolution renders it impractical for investigation of dynamic processes [1]. We devised a novel method that enables the use of scanning probe microscopy for recording the periodic motion at nanoscale with submillisecond resolution. We demonstrate the method by visualizing periodic motion of the vortex lattice in NbSe2 , induced by ac magnetic field with scanning tunneling microscopy. Direct observation of this process reveals different dynamical modes of the driven vortex lattice as well as the unforeseen intricacy of the vortex trajectories[2]. [1] G. Schitter, M. J. Rost, Mater. Today, 11, 40-48 (2008) [2] M. Timmermans, T. Samuely, B. Raes, J. Van de Vondel, and V. V. Moshchalkov, ACS NANO, 8, 2782-2787 (2014) 10 Thu 14:00 – 14:20 Zdeňka Hájková hajkovaz@fzu.cz Fyzikální ústav AV ČR Cukrovarnická 10/112, Praha 6, 16200 Z. Hájková, M. Ledinský, A. Vetushka, J. Stuchlík, M. Bouša, O. Frank, A. Fejfar Local conductivity measurements of CVD graphene transparent electrode for thin film silicon solar cells Transparent electrodes are essential components in many photovoltaic and electronic devices. Recently, graphene has attracted significant interest as a promising transparent, flexible, and cost-effective electrode with low sheet resistance (down to 10–30 Ω/square). In this paper we present local electrical properties of graphene placed on hydrogenated microcrystalline silicon (µc-Si:H) thin film. Graphene prepared by chemical vapor deposition (CVD) on Cu substrate was transferred onto µc-Si:H layer by the commonly used dry transfer. The µc-Si:H film had high surface roughness, due to the round µc-Si:H grain caps (with diameter from 100 nm up to more than 1 µm) in the otherwise flat amorphous silicon surroundings. Differences in local photo-conductivity (silicon film was illuminated by AFM detection laser) between grains and amorphous part were in orders of magnitudes [1]. The quality of the transferred graphene was analysed by Raman micro-spectroscopy. Moreover, local electronic properties were mapping by conductive atomic force microscopy (C-AFM) in PeakForce TUNA mode, as well as in contact mode. It was shown that graphene layer was divided into µm-large graphene flakes with local current value nearly constant for the individual flake and corresponding to the flake area. Graphene flakes (cracks) were observable also by scanning electron microscopy (SEM). As no contrast in conductivity was found between individual microcrystalline grains and amorphous silicon, we can suppose very good electrical contact between graphene and the µc-Si:H film which is principal for photovoltaic and other electronic applications of graphene. [1] Ledinsky et al., PSS RRL 5 (2011) 373–375. Thu 14:20 – 14:40 Dušan Novotný MT-M company presentation Thu 14:40 – 15:00 Matěj Hývl hyvl@fzu.cz The Academy of Sciences of the Czech Republic, Institute of Physics ASCR, v. v. i. Cukrovarnická 10/112, Praha 6 M. Hývla , M. Mullera , S. Misrab , P. Roca i Cabarrocasb , M. Kratzerc , C. Teichertc , A. Fejfara Correlative microscopy on radial junction solar cells based on silicon nanowires a) Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnická 10, 162 00 Prague 6, Czech Republic b) Laboratoire de Physique des Interfaces et des Couches Minces (LPICM), CNRS , Ecole Polytechnique, 91128 Palaiseau, France c) Institute of Physics, Montanuniversitaet Leoben, Franz-Josef-Strasse 18, 8700 Leoben, Austria Radial junction solar cells based on silicon nanowires offer a self-organized, optically thick and geometrically thin structure with low fabrication cost and fast growth rate [1]. During our previous investigations of electronic properties of Si nanowire-based RJ solar cells grown by plasma-assisted vapour-liquid-solid (VLS) process we have reported on an inhomogeneous distribution of conductivities observed for individual neighbouring RJs by atomic force microscopy (AFM) [2]. Correlation between several AFM techniques and scanning electron microscopy of identical nanowires was sought in order to identify the reason for conductivity variations. This can be achieved by creating a group of three indents arranged in triangles that can serve as coordinate 11 systems for triangulation on samples, enabling correlative microscopy even in instruments which were not designed for it. This approach also enables localization of the same positions on samples after repeated mounting in various microscopes with a precision better than 50 nm. Using sets of microscopic indents as reference points for the local coordination system, we managed to correlate the results from scanning electron microscopy, Kelvin probe force microscopy and PeakForce conductive AFM technique on the same place of our samples, looking for the relation between the measured current and the potential photoresponse. The surface potential signal exhibits inhomogeneity in values for individual radial junctions similar to that observed in the measured conductivity. [1] S. Misra et al., Journal of Physics D: Applied Physics. 47 (2014), 39301. [2] A. Fejfar et al., Sol. Energy Mat. Sol. Cells. (2015) Thu 15:00 – 15:20 Jan Čermák cermakj@fzu.cz Fyzikální ústav AV ČR, v.v.i. Na Slovance 2, Praha 8, 182 00, ČR Jan Čermák, Takatoshi Yamada, Kristína Ganzerová, Bohuslav Rezek Correlated SPM characterizations of CVD graphene on copper and cuprous oxide Chemical vapor deposition (CVD) can produce graphene in large scale. Yet it is still not ready for real applications and needs further enhancements to achieve uniform high quality graphene coverage. The microscopic characterization of a thermal CVD graphene on a copper (Cu) foil reveals that graphene is formed on a clean Cu as well as on areas covered with cuprous oxide (Cu2 O). Yet its electrical and material properties differ accordingly to the underlying material as observed by correlated measurements by Raman spectroscopy micro-mapping, conductive atomic force microscopy and Kelvin probe force microscopy. Interpretation of the experimental data set as a result of a substrate doping effect is discussed. Thu 15:20 – 15:40 Filip Münz munz@physics.muni.cz CEITEC MU Kotlářská 2 Filip Münz, Jiří Novák Organic semiconductors in self-organized layers Semiconducting materials based on phthalocyanine can be thoroughly studied using SPM techniques, crucial point being their adhesion on the substrate. Mono-molecular layers created by Langmuir-Blodgett procedure were analyzed also for their optical properties with the aim of a sub-diffraction resolution using tip-assisted methods. Thu 15:40 – 16:00 Jan Vávra vavra@jpk.com JPK Instruments AG JPK Instruments AG, Bouchéstrasse 12, 12435 Berlin, Germany Heiko Haschke, Dimitar Stamov, Torsten Jähnke High-Resolution and High-Speed Atomic Force Microscopy Simultaneous to Advanced Optical Microscopy In recent years, atomic force microscopy (AFM) has become a well-established technique for single molecule studies and even sub-molecular scale research. Several new developments in terms of faster AFM imaging and imaging modes, based on the phase or frequency, have been established in order to decrease the cantilever response time and increase the AFM’s scan speed, e.g., for studying molecular dynamics. 12 R The novel NanoWizard ULTRA Speed AFM combines the latest scanner technologies and compact design allowing a full integration of AFM into advanced commercially available optical microscopy. Thus, fast AFM imaging of approximately 1 frame per second can be seamlessly combined with methods such as, fluorescence, confocal, TIRF, STED microscopy and many more. Individual molecule dynamics can now be studied with AFM and simultaneously with optical microscopy by applying JPK’s tip scanner technology. With JPK’s HyperDriveTM sub-molecular resolution is achieved even on soft samples imaged in liquid environments. It allows for imaging with smallest amplitudes of often approximately 0.2 nm for lowest tip-sample interaction. Topographical images of membrane proteins and DNA-origami are presented. It has been shown that the phase response in phase modulation AFM (PMAFM) is faster allowing higher R imaging speeds for the study of molecule kinetics. In conjunction with JPK’s NanoWizard ULTRA Speed AFM, a dynamic biomechanical study of Bacteriorhodopsin (bR) when interacting with photons will be discussed. More than half a century after the first high-resolution electron microscopy images of collagen type I R banding of 67 nm have been reported, now with the NanoWizard ULTRA Speed AFM we could gain a high-resolution temporal insight into the dynamics of collagen I fibril formation and its characteristic 67 nm banding hallmark. The literature still abounds with conflicting data regarding the models of its fibril formation, structural intermediates, and kinetics. AFM is the only currently available high-resolution imaging technique amongst many to offer insight into the collagen I fibrillogenesis by operating in situ. The described technique could be instrumental for future studies of the structural dynamics of protein systems, etc. The systems newly gained flexibility will also be demonstrated on a study of living fibroblast cells directly imaged in their culture petri dish at 37 degrees C. Here, the dynamics of individual membrane structures is investigated with AFM while simultaneously observing the individual living cell with optical phase contrast. The unambiguous correlation between AFM and optical microscopy is achieved by the DirectOverlayTM technique. Thu 16:20 – 17:05 Deb Roy debdulal.roy@npl.co.uk National Physical Laboratory, UK Hampton Road, Teddington, Middlesex, TW11 0LW Nano-optics for Nano-chemistry and Nanostructures Heterogeneity and inhomogeneity are integral parts of most functional materials. Transmission electron microscopy (TEM), generally the technique of choice due to its atomic resolution, works only in vacuum. Near-field optical tool such as tip-enhanced Raman spectroscopy, however, allows conducting measurements on local nanoscale surfaces in ambient environments. In this talk two examples of measurements using nano-optics will be presented: one that measures chemistry on single electro-chemically active sites on a catalytic surface, paving the path for real-time investigation of catalytic reactions, and the other maps individual defects in 2D materials such as graphene. Thu 17:05 – 17:25 Marek Černík mc@uniexport.co.cz Witec, Uni-Export Instruments Correlating 3D Raman Imaging with Scanning Microscopy Techniques Company presentation 13 Thu 17:25 – 17:45 Petr Klapetek pklapetek@cmi.cz Czech Metrology Institute Okružní 31, Brno, 638 00 Petr Klapetek, Radek Šlesinger, Miroslav Valtr FDTD modeling for localised Raman measurements Light-matter interaction at nanoscale is source of information in many promising characterization techniques (e.g. Tip Enhanced and/or Surface Enhanced Raman Microscopy). Theoretical treatment of all these method is often based on assumption that materials forming surfaces are ideal (flat, non-contaminated, with optical properties known from databases). Realistic materials are however not ideal and we can observe many different surface irregularities. Most frequently it is surface roughness, originating from manufacturing process, like sputtering. In this contribution we present numerical approach for modeling performance of different methods related to localised Raman spectroscopy in presence of surface roughness. The approach is based on combination of material deposition modeling and fast Finite Difference in Time Domain solver of Maxwell equations based on use of graphics cards. Examples will be taken from the field of Tip Enhanced Raman Spectroscopy and micro Raman measurements. Thu 17:45 – 18:05 Daniel Haško hasko@ilc.sk International Laser Centre Ilkovičova 3 Daniel Haško, Pavol Písečný The combination of scanning probe and optical interferometric microscopic methods for characterization of materials and components for FIC. The properties of photonic structures and parameters of components for photonic integrated circuits (FIC) are highly dependent on the surface roughness, defects within the used material and the geometric proportions. For mapping and evaluation of surface morphology and the geometrical dimensions of realized structures the precise scanning probe and interfererometric microscopy methods have been used. The determination of exact dimensions of manufactured structures allow the investigation of the impact of size and shape of the accomplished devices on the optical properties and optimize their parameters and, in addition to other, identify critical steps in the fabrication technology. By using organic materials in photonic structures opens the new possibilities for applications of developed components, due to the functionalities that were not possible to achieve with inorganic materials. Acknowledgement This work was financially supported by Scientific Grant Agency of the Ministry of Education, Science, Research and Sport of Slovak Republic No. VEGA-1/0907/13 and by Competence Center for SMART Technologies for Electronics and Informatics Systems and Services, ITMS26240220072, funded by the Research & Development Operational Programme from the ERDF. Thu 18:05 – 18:25 Dušan Novotný MT-M company presentation 14 Fri 9:30 – 10:15 P.-Olivier Chapuis olivier.chapuis@insa-lyon.fr CETHIL – CNRS, INSA Lyon, UCBL Campus La Doua-Lyon Tech, 69621 Villeurbanne (Lyon), France P.-Olivier Chapuis, M. Massoud, A. Assy, S. Gomès Scanning thermal microscopy: micro to nanoscale thermal properties Many material engineering processes, such as those of electronics, and the grand energy challenge require improving heat dissipation or thermal insulation, therefore the analysis of thermal properties at all scales is more than welcome. It is especially the case because Fourier’s law of heat conduction breaks down at the 10-100 nm scale in crystalline solids and because interface effects may become dominant due to the increase of the surface-to-volume when the involved size decreases. Usual non-contact thermal techniques (thermoreflectance, Raman thermometry, etc.) are based on optical interaction with matter limited by Rayleigh’s diffraction at few hundreds of nanometers. As a consequence, atomic force microscopy-based tools appear promising for thermal investigation. Scanning thermal microscopes (SThM), based on tips instrumented with thermal sensors such as resistive thermometers or thermocouples, are now well-established techniques that deliver qualitative information, but the road to quantitative data is still to go [1]. This is due to the complexity of the tip-sample heat transfer which does not only depend only on the mechanical point contact: heat is also transferred through the air, through the water meniscus around the contact and through near-field thermal radiation. In this talk we will analyze these heat transfer mechanisms and present examples of thermal characterizations of nanostructures or complex materials, which encompass in particular thin films, porous and irradiated materials, chessboard-like surfaces. We will especially pay attention to the SThM calibration issues and to the trade-off between spatial and thermal resolutions. [1] S. Gomès, A. Assy, and P.-O. Chapuis, Scanning thermal microscopy: a review, Physics Status Solidi (a), to appear in March 2015 Fri 10:15 – 10:35 Jan Vaniš vanis@ufe.cz Ústav Fotoniky a Elektroniky AV ČR, v.v.i Chaberská 57, Praha 8, 182 51 Scanning thermal microscopy of thin PLD layers Materials with high possible figure of merit ZT are of high interest as a promising candidates for thermoelectric applications. However evaluation of their thermal conductivity deals with a lot of difficulties when the sizes shrink. One of the promising method for their characterization is scanning thermal microscopy. In our contribution measurement experiences with commercial Picocal/Veeco Multimode scanning thermal microscope will be presented. The brief information about system development, thermal probes characterizaton, types of till now used thermal probes and troubleshooting with all above mentioned will be given. The rest of the talk will be focused on measured results on different thermoelectric materials (Bi2 Te3 , skutterudites) deposited in variety of thicknesses by pulsed laser ablation (PLD) from sintered material targets. The project has been supported by Czech Grant Agency under P108/13-33056S. Fri 10:35 – 10:55 Jan Martinek jmartinek@cmi.cz Czech Metrology Institute Okružní 31, Brno, 638 00 J. Martinek, P. Klapetek Topography artifacts compensation in scanning thermal microscopy on rough surfaces Thermal conductivity contrast images in Scanning Thermal Microscopy (SThM) are often distorted by ar15 tifacts related to local sample topography. This is namely pronounced on samples with sharp topographic features, on rough samples, and while using larger probes, e.g. Wollaston wire based ones. Topography artifacts can be so high that they can even obscure local thermal conductivity variations influence on measured signal. The presented method for compensation of topography artifacts is based on 3D Finite Element Modeling of the probe-sample interaction. Fri 11:15 – 11:35 Vilma Buršíková vilmab@physics.muni.cz Faculty of Science, Masaryk University Kotlářská 2, Brno Vilma Buršíková, Jiří Buršík Quantitative mapping of mechanical properties using quasistatic and dynamic nanoindentation and AFM techniques The aim of the work is to compare the results of several nanoindentation approaches for the assessment of hardness and elastic parameters using both the quasi-static indentation and the dynamic modulus mapping method. The results of quasi-static and dynamic nanoindentation were carried out for two different materials, such the nanocomposite polymer coating (silicon-oxide particles in amorphous SiOCH matrix) and copper-cobalt alloy with cobalt content of 4 at.%. The modulus mapping capability was applied to obtain quantitative maps of the storage and loss stiffness and the storage and loss modulus. The modulus mapping combines the in-situ imaging capabilities with the ability to perform nanodynamic mechanical analysis. During the imaging process, the system continuously monitors the dynamic response of the sample to the oscillating load as a function of the position. Therefore, at each image pixel (typically 256 × 256 pixels), the storage and loss moduli are found if the geometry of the indenter is known. At the same time one can also gain information about the sample surface morphology. The modulus mapping results were compared with quantitative maps of stiffness, elastic modulus and work of adhesion carried out using atomic force microscopy technique. Fri 11:35 – 11:55 Ondřej Číp ocip@isibrno.cz Ústav přístrojové techniky AV ČR, v.v.i. Královopolská 147, Brno Scale linearity testing of a laser interferometer of metrological AFM with the optical frequency comb Scale linearity of laser interferometers plays important role at scanning probe microscopes with metrological traceable positioning. Interferometer scales can be distorted with some imperfections in the optical setup, error signals in the processing chains, and mechanical deviation caused by temperature. The scale linearity of standard two-beam interferometers should be verified before utilizing at positioning stage of the microscope. Our measuring gauge is based on a length etalon with a variable distance where the quantity length is locked to a precise passive optical cavity. The etalon has a piezoelectric transducer as the actuator. The passive cavity length is monitored with a tunable laser and optical frequency comb locked to a time standard (active H-maser). A beat-note the laser and a comb tooth is used in a feedback. We present scheme, experimental setup, and records of scale non-linearity testing of the homodyne laser interferometer. 16 Fri 11:55 – 12:15 Vlastimil Píč pic@fzu.cz Fyzikální ústav AV ČR, v. v. i. Na Slovance 1999/2, Praha Vlastimil Píč, Antonín Fejfar Educational Macromodel of AFM Macromodel of AFM is a computer-controlled electromechanical device imitating a function of a real AFM microscope, but in macroscale. It enables to demonstrate for the students the function and behaviour of a real device, test its response, features and algorithms. Fri 12:15 – 12:35 Josef Lazar joe@isibrno.cz Ústav přístrojové techniky AV ČR, v.v.i. Královopolská 147, Brno Interferometric coordinate position sensing with semiconductor laser sources We report on improved design of the metrological Scanning probe microscope with high-precision interferometric position sensing for dimensional metrology and nanometrology. This research exploits previous results in the field of laser standards of optical frequencies and the methodology of interferometric metrology of length together with detection systems of interference signals and their processing at the ISI and the production technology of precise optical components at Meopta – optika. We investigated the possibility of replacement of traditional He-Ne lasers with solid-state Nd:YAG and semiconductor DBR lasers. We developed a compact, solid-state Nd:YAG frequency stabilized laser referenced to iodine transitions and tested a 634 nm semiconductor iodine-stabilized laser through evaluation of the laser optical frequency noise. Fri 12:35 – 12:55 Michal Urbánek urbanek@isibrno.cz Ústav přístrojové techniky AV ČR, v.v.i. Královopolská 147, Brno Michal Urbánek, Vladimír Kolařík, Stanislav Krátký, Miroslav Horáček, Milan Matějka, Petr Meluzín, Jana Chlumská AFM characterization of structures prepared by e-beam: on the border between micro and nano In this contribution we summarize the use of atomic force microscopy for evaluation of structures prepared by e-beam writing (mainly diffractive gratings with various periods, depth and relief). While period is defined precisely, we are interested in depth and relief of such structures. From perspective of e-beam writing process some issues of AFM method are discussed. 18
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