ALTECH 2014 - Analytical techniques for precise characterization of nanomaterials
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Metrology is a prerequisite for the development of novel materials on the nanoscale. It supports the correlation of material properties and functionalities. The expected contributions should demonstrate how innovative analytical techniques enable a deep understanding of new materials. This symposium will be organized by major European national metrology institutes and the Belgian research institute Imec.
ALTECH is a series of conferences that started in 1989. The conference was offered as a satellite or symposium of semiconductor conferences in Europe or, on occasion, in the U.S. The peer-reviewed ALTECH 2014 symposium proceedings will be published in Physica Status Solidi (a) and (c). In conjunction with the general ALTECH 2014 symposium, a workshop and a training course, both originating out of several European Metrology Research Program (EMRP) projects, will be included.
Nanomaterials have unique properties associated with their small dimensionality. Functional nanomaterials are rapidly finding wider use in modern technological products in many areas, for example, displays, energy conversion, energy storage, sensors and biosensors. Accurate characterization of nanoscaled materials is essential for the development of such innovative products. Conversely, properly engineered nanomaterials are currently seen as one of the most promising tools for high resolution optical microscopy.
Metrology for nanoscaled materials relies on the ability to measure in up to three dimensions over large areas and to measure material properties traceable to SI units. Furthermore, elemental compositions and chemical states are important. As the structures and dimensions are ‘nano’ or even atomic scale, the analytical techniques need to be developed beyond their current limits, requiring new innovative approaches to face state-of-the-art challenges.
This symposium will cover recent and innovative developments in analytical techniques that can provide precise characterization of materials and devices with nanoscale and/or atomic resolution. The objective is to highlight the capabilities of precise techniques for both the determination of the key structural and material parameters and for a better understanding of the functional properties. One major focus will be on the application of these techniques to new and complex materials systems with high potential of industrial impact, including nanoscaled objects (nanowires, quantum dots), nanostructured thin films of organic, hydrid or inorganic semiconductors, and functionalized surfaces (e.g. for the detection of molecules for biosensing). Demonstration of in-situ capabilities for a deeper understanding of the structure formation is expected. A special focus will be on complementary metrology in terms of using different analytical techniques with the aim of ensuring accuracy and traceability, i.e. the inclusion of a well-described uncertainty budget. As many of these techniques depend on modeling for achieving reliable results, effective material analysis and computational analysis of materials and thin layers are to be highlighted.
Hot topics to be covered by the symposium:
- X-Ray diffraction, tomography, scattering and spectrometry based applications on advanced materials and in nanoscience
- Recent developments of ion beam techniques for characterization of lateral and vertical thin films
- New developments for optical spectroscopic measurements, large-area nanostructured high-refractive index materials measurement and modeling, optical scatterometry by coherent light
- Techniques for thermal characterization of thin films
- Methodologies for thin films, nanostructure, interfacial and nanostrain characterizations of semiconductor and advanced material systems
- Scanning probe techniques for high resolution characterization of organic, hybrid and inorganic semiconductors
- Analytical techniques for characterization of surface chemistry
- Characterization of functionalized surfaces for e.g. biosensing and bioanalytics
- Novel instrumentation for e.g. nanoanalysis, next generation of highest resolution microscopy including near-field methods, characterization of metallic and dielectric based superlenses
- Ultra-trace analysis using complementary metrology
- Reference and calibration samples for nanometrology
List of invited speakers:
- Wim Coene, ASML, The Netherlands, "Optical Metrology for Photo-Lithography"
- Thierry Conard, IMEC, Belgium, “Nano-scale feature analysis: Achieving high effective lateral resolution with micro-scale material characterization techniques”
- David Ginger, University of Washington, USA, “Imaging Structure/Function Relationships in Nanostructured Solar Cells“
- Séverine Gomes, CETHIL, France, “Thermal nanometrology and scanning thermal microscopy”
- Jaime Gomez Rivas, FOM, The Netherlands, “Plasmonics for Solid State Lighting”
- Poul-Erik Hansen, DFM, Denmark, “Polarization dependent measurement of nanostructured surfaces”
- Ludger Koenders, PTB, Germany, ”Dimensional metrology for surface analytics”
- Jaecheol Lee, Samsung Advanced Institute of Technology, South Korea, “Characterizations of the oxide semiconductor and OLED materials using combination of surface analysis methods"
- Maria Luisa Polignano, ST Microelectronics, Italy, “A comparative analysis of different measurement techniques to monitor metal and organic contamination in silicon device processing”
- Eddy Simoen, University Ghent and Imec, Belgium, “Towards single-trap spectroscopy: Generation-Recombination noise in UTBOX SOI nMOSFETs”
- Wolfgang Unger, BAM, Germany, “Metrology for Surface Chemical Analysis at the Nanoscale: Status and Challenges”
The conference proceedings will be published in physica status solidi (c). Excellent manuscripts will be selected for physica status solidi (a). The online submission for the conference proceedings will open mid-April 2014. The manuscripts have to be prepared following the pss (c) guidelines and template. The deadline for the submission of manuscripts is May 23, 2014 just prior to the ALTECH 2014.
Phone: +49 (0)30 3481 7170
Fax: +49 (0)30 3481 7102
Fernando Araujo de Castro
National Physical Laboratory
TW11 0LW Teddington
Phone: +44 20 8943 6357
Omar El Gawhary
VSL Dutch Metrology Institute
2629 JA Delft
Phone: +31 (0) 15 2691714
Fax: +31 (0) 15 2612971
Czech Metrology Institute
638 00 Brno
Phone: +42 545 555 111
Fax: +42 545 555 183
Phone: +32 16281328
Fax: + 32 16281213
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Authors : E. Salas-Colera 1-2, A. Mu?oz-Nova l1-2, C. Heyman 3, J. Rubio-Zuazo 1-2 and G.R. Castro 1-2
Affiliations : 1 Spanish CRG BM25 Beamline SpLine at the ESRF, Grenoble, France; 2 Instituto de Ciencia de Materiales de Madrid-ICMM/CSIC, Madrid, Spain; 3 CAO-DAO Heyman 5, place de Gordes,38000 Grenoble, France.
Resume : A new experimental set-up has been designed and performed for synchrotron X-ray powder diffraction in transmission geometry (capillary) for in situ solid-gas reactions and processes at isobaric and isothermal environment. One of the novel elements of this set-up is the home designed rotor sample holder which permits spinning the capillary and keeping constant the gas atmosphere in the sample. The temperature and pressure of the sample can be set and kept stable in the ranges from 77 to 1000 K and from 1 to 103 mbar, respectively, from a vacuum condition < 10-3 mbar. The studies of gas induced structure deformation in a nanoporous material such as a zeolitic imidiazol framework (ZIF-8) by the gas adsorption at cryogenic temperature at isothermal/isobaric conditions have been carried out to test capacities of this new experimental setup. Direct evidences of structure deformation by the adsorption of Ar and N2 have been observed in situ, making this set-up suitable for direct structural analysis at in operando conditions. Therefore, the presented results demonstrate the feasibility of this novel experimental station for the characterization at real time of solid-gas reactions and other solid gas processes by high resolution powder diffraction. This set-up has been developed and installed in the Spanish CRG BM25-SpLine beamline at the European Synchrotron Radiation Facility (ESRF).
Authors : L. Anklamm, W. Malzer, C. Schlesiger, S. Schuh, and B. Kanngießer
Affiliations : Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin, Germany
Resume : High resolution X-ray emission spectroscopy (XES) is an emerging method for the investigation of the electronic structure of materials. Measurement of the band structure is one of the applications. Nowadays, research relying on XES is dominated by experiments using synchrotron radiation. While current experimental setups allow for advanced experiments, the high barrier accessibility hampers the exploitation of the entire potential of XES. With this contribution, we present first experimental results and characteristics of a laboratory based XES spectrometer. It combines high efficiency with high spectral resolving power. In favorable situations, a complete spectrum of the Kβ multiplett of a transition metal can be aquired within half an hour and with a spectral resolution E/ΔE of around 2000. Nano-scaled layer require longer acquisition times. Taking an XES spectrum of a Fe-layer of 300 nm thickness takes around 10 hours in the current configuration. In future setups, the power of the X-ray tube, and thus the sensitivity of the instrument, could be scaled up by a factor of 10. We will present the principle of the XES laboratory spectrometer and results of demonstration and characterization experiments. The properties and peculiarities of the spectrometer and the spectra obtained will be discussed as well as possible future developments and improvements.
Authors : Naoki Komatsu, Li Zhao, Hongmei Qin, Takahide Kimura
Affiliations : Shiga University of Medical Science
Resume : Organic functionalization of nanoparticles has been attracting significant interest to impart multiple functions to the nanoparticles, in particular, for their biological and medicinal applications. Among them, diamond nanoparticle, so called nanodiamond (ND), has been recognized as one of the best platforms due to the non- or low-toxic property and the organic character enabling the covalent functionalization. In this context, we demonstrated multi-step organic transformations on the ND surface  to impart the requisite functions as ND-based drug carrier [2,3] and imaging probe . The functionalities introduced onto the ND surface were well characterized qualitatively and quantitatively by solution-phase NMRs, IR and Raman spectroscopies, and thermogravimetric and elemental analyses. Although IR has been mainly used for this kind of characterization, we realized more precise characterization of functionalized nanoparticle by use of various kinds of analytical methods.  L. Zhao, N. Komatsu, Angew. Chem. Int. Ed., 50 (6), 1388-1392 (2011)  L. Zhao, N. Komatsu, X. Chen, submitted  L. Zhao, H. Kojima, N. Komatsu, submitted  L. Zhao, A. Shiino, N. Komatsu, J. Nanosci. Nanotechnol. in press
Authors : D. Fischer, A. Nooke, A. Hertwig, M. Weise, U. Beck, M. Kormunda (1)
Affiliations : BAM Federal Institute for Materials Research and Testing, Division 6.7, Unter den Eichen 87, 12205 Berlin, Germany; (1)J.E. Purkyne University, Faculty of Science, Department of Physics, Ceske mladeze 8, 40096 Usti nad Labem, Czech Republic
Resume : During the last decades, ellipsometry has become more and more important, parallel with the development in surface science. By using it as a key technique for the analysis of thin films, it gives access to essential surface specific information like layer thicknesses. Additionally, with applying a proper model, the dielectric function of each layer can be extracted which allows a deeper understanding of its properties. In the presented work, new non-invasive gas sensors based on the SPR-effect with ellipsometric readout were build and characterized. The sensor consists of a gold layer (~40 nm) top-coated with a doped metal-oxide (Tin Oxide, ~5 nm). The coating was attached by sputtering with doped targets with different doping concentration and doping material. In the past, it could be shown that, without the top-coating, these type of sensors can detect various gases in sensitivities down to the ppm range (in air). With the help of the doped-metal oxide, the sensitivity increases dramatically by a factor of 100. Furthermore, a selectivity for specific gases was observed which depends on the doping of the coating. To find a relation between the layer properties and the sensitivity of the sensing process, the dielectric function is characterized by spectroscopic ellipsometry with respect to the deposition parameters and the dopent concentration.
Authors : Alina Zoladek-Lemanczyk (1), Jong Soo Kim (2), Ji-Seon Kim (2), James Blakesley (1), Fernando A. Castro (1)
Affiliations : (1) - Materials Division, National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom; (2) - Department of Physics & Centre for Plastic Electronics, Imperial College London, London SW7 2AZ, United Kingdom
Resume : Orientation of molecules and bonds within matter is often a major factor determining its properties. Order in molecular orientation between and within domains plays a critical role in determining the optical and electronic properties of organic semiconductor films resulting in anisotropic energy levels and charge mobilities. For example, in polymers, if molecular packing is sufficient, electronic orbitals will delocalize along the polymeric backbone or couple strongly between molecules, allowing for efficient charge transport along specific directions in the material and making it suitable for use in devices such as light-emitting diodes, transistors or solar cells. Therefore understanding and quantifying the molecular alignment of functionalized materials and conjugated polymers within thin-film samples is essential for a complete picture of their optical and transport properties for the continuous development of optoelectronic device applications. Polarization-dependent Raman microscopy is a powerful technique to perform both structural and chemical analyses with submicron spatial resolution. Raman data can also be collected in situ, which makes this technique even more attractive as a non-invasive device probe. We report here on the practicality and limitations of Raman polarisation measurements as a probe of molecular orientation in organic thin films for transistor applications. Challenges in correcting for system calibration will be discussed and a simple model for the effect of molecular orientation on measurement results will be introduced in order to facilitate validation of results.
Metrology for More than Moore Technologies : Thierry Conard and Matthias Müller
Authors : M.L. Polignano, D. Codegoni, S. Grasso, I. Mica, G. Borionetti, A. Nutsch
Affiliations : ST Microelectronics, via Olivetti, 2, 20864 Agrate Brianza (MB) Italy; MEMC Electronic Materials SpA, a Sunedison Company Viale Gherzi ,31, 28100 Novara Italy; Physikalisch-Technische Bundesanstalt, Abbestr.2-12, 10587 Berlin, Germany
Resume : A few key techniques for the analysis of contamination in silicon are compared for their ability to detect different impurities. Both metal and organic contamination is included in this study. In addition, common contaminants and elements recently introduced in the fabrication process are considered. For what concerns metal contamination, it is shown that different approaches are required depending on the in-depth distribution of the contaminant and hence on its diffusivity. Copper, iron, molybdenum and tellurium are chosen as the examples of contaminants with different diffusivity and solubility properties. TXRF, recombination and generation lifetime measurement techniques, DLTS and capacitance vs. voltage measurements are compared. The detection of slow diffusers is found to be very critical, because a very low dose may result in a non-negligible concentration in the device region. As a consequence, the sensitivity per unit area required for these elements is difficult to reach with surface techniques such as TXRF. On the other hand, very fast diffusers such as copper can be hardly revealed in the solid solution in silicon. Copper in silicon can be revealed at the oxide-silicon interface by TOF-SIMS measurements, or by surface generation velocity measurements with the Zerbst method. For what concerns organic contamination, surface recombination velocity, interface state density measurements by the conductance method, MOS-DLTS and gate oxide integrity tests were compared. The most relevant effects of organic contamination were observed by electrical stress of the oxide. Indeed, the fraction of capacitors with degraded breakdown voltage increased dramatically in wafers with intentional organic contamination.
Authors : E. Simoen1,2, B. Cretu3, W. Fang1,4,5, M. Aoulaiche1,6, J.-M. Routoure7, R. Carin7, S. dos Santos7, J. Luo4, C. Zhao4, J.A. Martino8 and C. Claeys1,5
Affiliations : 1Imec, Kapeldreef 75, B-3001 Leuven, Belgium 2Depart. Of Solid-St. Physics, Ghent University, Gent, Belgium 3ENSICAEN, UMR 6072 GREYC, F-14050, Caen, France 4Key Laboratory of Microelectronic Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China 5E.E. Dept., KU Leuven, Leuven, Belgium 6presently at Micron Technology Belgium, imec Campus, Belgium 7 University of Caen, UMR 6072 GREYC, F-14050, Caen, France 8LSI/ PSI/USP - University of S?o Paulo, SP, Brazil
Resume : Performing defect spectroscopy in nano-scaled structures is a challenging endeavor. One technique that appears to be very suited for this task is low-frequency (LF) noise spectroscopy . It is well established that in the ultimate limit, the LF noise spectrum is dominated by a single trap, giving rise to a so-called Random Telegraph Signal (RTS), whose up and down time constants can be studied to derive the defect level parameters . At the other end of the scale, large MOSFETs may exhibit Generation-Recombination (GR) noise, which corresponds with a Lorentzian spectrum. The corner frequency f0 of such a Lorentzian can be investigated as a function of the temperature and analyzed in an Arrhenius diagram, yielding the activation energy and the capture cross section of the underlying GR centers in the depletion region of the semiconductor [3,4]. In this paper, the principles of GR noise spectroscopy will be outlined, based on n-MOSFETs fabricated in Ultra-Thin Buried Oxide (UTBOX) Silicon-on-Insulator (SOI) substrates. As will be shown, the fully depleted (FD) nature of the devices offers some unique opportunities to study deep levels in the thin silicon film . In fact, it is demonstrated that the Lorentzians observed in the noise spectra correspond with only one or at most a few traps in the film, so that the corresponding RTS becomes visible in the time domain . It will be shown that analyzing the RTS parameters (current amplitude ID; capture and emission time constant) as a function of the operation biases enables to determine the lateral and vertical position of the GR center in the silicon film . References  N. Lukyanchikova, in Noise and Fluctuations Control in Electronic Devices, edited by A. Balandin, American Scientiﬁc, Riverside, CA, 2002.  M.J. Kirton and M.J. Uren, Adv. in Phys., 38, 367 (1989).  I. Lartigau, J.M. Routoure, W. Guo, B. Cretu, R. Carin, A. Mercha, C. Claeys, and E. Simoen, J. Appl. Phys., 101, 104511-1 (2007).  S. D. dos Santos, B. Cretu, V. Strobel, J.-M. Routoure, R. Carin, J.A. Martino, M. Aoulaiche, M. Jurczak, E. Simoen and C. Claeys, Solid-St. Electron. (accepted).  A. Luque Rodr?guez, J.A. Jim?nez Tejada, S. Rodriguez-Bol?var, M. Aoulaiche, C. Claeys and E. Simoen, IEEE Trans. Electron Devices, 59, 2780 (2012).  E. Simoen, M. Aoulaiche, S. D. dos Santos, J.A. Martino, V. Strobel, B. Cretu, J.-M. Routoure, R. Carin, A. Luque Rodr?guez, J.A. Jim?nez Tejada, and C. Claeys, ECS J. of Solid St. Science and Technol., 2, Q205 (2013).  W. Fang, M. Aoulaiche, E. Simoen, J. Luo, C. Zhao, and C. Claeys, submitted to IEEE Electron Device Lett.
Authors : D. Ohori(1), Y. Murayama(1), K. Kondo(1), M. M. Rahman(2), M. E. Syazwan(2), T. Okada(2), S. Samukawa(2), A. Fukuyama(1), and T. Ikari(1)
Affiliations : (1) DEEE, University of Miyazaki, 1-1 Gakuen Kibanadai-nishi, Miyazaki, Japan (2) Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Japan
Resume : Semiconductor nanostructure has recently received broad attention for applying to photovoltaic cell with advanced performances. Miniband formation between the quantum dots is a key feature for materializing higher efficiency. It is then necessary to control precisely the sizes and their intervals. Although it is very difficult to grow well-arranged quantum dots by a conventional technique, such as StranskiKrastanov growth mechanism, we succeeded for fabricating the exactly arranged Si nanodisk (Si-ND) of dimensions around sub-10-nm embedded in SiC matrix by our original top-down process with bio-templates and neutral beam etching . Therefore, the carrier transport process in the Si-ND array structure could be investigated in terms of the lifetimes of photoexcited carriers by using a microwave photoconductivity decay method. Among the five types of Si-ND array structure samples, longest lifetime of 3.4 μsec was observed for the sample with the disc size of 4-nm-thick/6.4-nm-diameter and the spacing of 2 nm along the thickness direction. We considered that the observed long carrier lifetime is due to decrease of the carrier recombination thanks to the miniband formation, say coupling the wave functions, along the thickness direction. The confirmation of the miniband formation of well-arranged nanodisk structure indicates the solar cell efficiency might be further increased by our sample growth technique.  S. Samukawa, et al., Appl. Surf. Sci. 253 (2007) 6681
Authors : J.L.Colaux, P.Hönicke, C.Jeynes, B.Beckhoff
Affiliations : University of Surrey Ion Beam Centre, Guildford GU2 7XH, England; Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin, Germany
Resume : Fundamental parameter (FP) based X-ray spectrometry (XRS) is very well suited for quantitative analysis of nanoscaled materials: this method is beneficial especially when no reference samples with sufficient quality are available or when the layer systems are complex. However, for quantitative investigations of elemental concentrations in unknown specimens by XRS, exact knowledge of the FPs is essential. These parameters include e.g. the fluorescence yields, the absorption cross sections or Coster-Kronig transition probabilities. For most chemical elements, only calculated data with unknown or estimated uncertainties are available. The experimental determination of such parameters is challenging, especially for elements where free standing thin foils are not available. Standard Ga-implanted Si wafers were prepared where the implanted dose was certified by Rutherford backscattering spectrometry (RBS) at 1% absolute accuracy : these samples were used to determine the product of the photoionization cross-section and the fluorescence yield of the Ga-K edge. The reliability of this result was estimated by constructing a formal uncertainty budget. The XRS experiments were carried out using the calibrated instrumentation of the Physikalisch-Technische Bundesanstalt at the BESSY II laboratory .  J. L. Colaux and C. Jeynes, Analytical Methods (2014) 6, 120-129.  M. Kolbe, P. Hönicke, M. Müller, B. Beckhoff, Phys. Rev. A (2012) 86, 042512.
Authors : 1 V.K. Egorov, E.V. Egorov, 2 E.M. Loukiantchenko
Affiliations : 1 IMT RAS, Chernogolovka, Moscow District, 142432 Russia 2 OOO Poljus, Saint-Petersburg, Russia
Resume : Historically, the mass-spectrometry methods form the basis for the ultra-trace analysis of materials. Its are characterized by multielements, high sensitivity and beautiful mass-resolution but the destructive procedures and show some problems at the element quantitative diagnostics. At the same time, there was elaborated the tools nondestructive method for ultra-trace multielemental material analysis, which shows the reassuming quantitative characteristics. It is the X-ray fluorescence analysis at external total reflection (TXRF) . The efficiency of the method is defined primarily by the exciting beam radiation density. Because of this, the best efficiency of TXRF diagnostics was obtained in case of the exciting beam formation by X-ray waveguide-resonators . These devices increase the radiation density in formed fluxes on four orders in comparison with ones formed by slit-cut flux formers. In result of it, element detection limits decrease on two orders. The work presents construction of TXRF experimental cell built on base of the original design waveguide-resonator and results of different objects diagnostics obtained about this cell application. There are discussed ways for waveguide-resonators property improving and its possible influence on the TXRF efficiency upgrading.  R. Klockenkamper. Total reflection X-ray fluorescence analysis. Wiley: New York. 245 p.  V.K. Egorov, E.V. Egorov // Adv. X-ray Chem. Anal. Japan. v44. 2013. pp. 21-40.
Authors : V.V.Andreev1, G.G.Bondarenko2, V.M.Maslovsky3, A.A.Stolyarov1, D.V.Andreev1
Affiliations : 1) Bauman Moscow State Technical University, Kaluga Branch. 4, Bazhenov St., Kaluga, 248600, Russia 2) National Research University Higher School of Economics, 20, Myasnitskaya Ulitsa, Moscow 101000, Russia 3) The state unitary enterprise of a city of Moscow Research-and-production centre "SPURT", Zelenograd, West of the 1-st proezd 4, 124460, Russia
Resume : In this study, a new technique of control current stress to investigation thin and ultrathin gate dielectrics of MIS structures is proposed. This technique allows to research charge processes which take place in gate dielectric of MIS structures and its interface under high-field and another stress situations (irradiation, plasma, hot carriers, etc.). The technique also may be used for testing thin gate dielectric defects. Unlike simple techniques, for example constant current stress and J-Ramp current stress, the developed technique for MIS structures applies of current stress with a special algorithm. At the same time characteristics of gate dielectric monitored by voltage time dependence, taking into account charging capacitance and charge trapping. Charging of MIS structure from inversion to accumulation modes or back way lets to receive low capacitive-voltage characteristics. Account charging capacitance of MIS structure and charge trapping in gate dielectric at injective mode lets considerably increase metrological characteristics of this technique and reduce inaccuracies. The models describing the change in the charge state of MIS structures, both in the charge capacity, and in the mode of injection of charge carriers were developed. Using these models let to choose optimal algorithm of current stress and increase measurement accuracy. This technique was used for research SiO2 and SiOxNy gate dielectrics with thick range 1-10 nm. The technique may be used for research of high-k and multilayer gate dielectrics.
Authors : Michael Kolbe, Philipp Hönicke, Matthias Müller, Burkhard Beckhoff
Affiliations : Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany
Resume : The further development of more complex materials with distinct properties needs an analysis independent from any reference material such as X-ray fluorescence analysis (XRF). For a reliable quantitative XRF the exact knowledge of atomic fundamental parameters involved is inevitable. In this work, fundamental parameters  including mass absorption and photo ionization coefficients, fluorescence yields, Coster-Kronig transition probabilities for several chemical elements are experimentally determined using the calibrated instrumentation of the Physikalisch-Technische Bundesanstalt (PTB) . The experiments were carried out in the PTB-laboratory as well as at the wavelength shifter beamline (BAMline) at the electron storage ring BESSY II, where monochromatized synchrotron radiation of high spectral purity up to about 100 keV is available. The knowledge of fundamental parameters with low uncertainties leads to significant improvements in quantitative XRF analysis in fact reference-based as well as reference-free.  M. Kolbe, P. Hönicke, M. Müller, B. Beckhoff, Phys. Rev. A 86 (2012), 042512  B. Beckhoff, J. Anal. At. Spectrom. 23 (2008), 845-853
Authors : Anna Charvátová Campbell, Petr Klapetek, Jan Martinek
Affiliations : Czech Metrology Institute
Resume : Measurement of local mechanical properties is an important topic in the ﬁelds of nanoscale device fabrication, thin ﬁlm deposition and composite material development. Nanoindentation instruments are commonly used to study hardness and related mechanical properties at the nanoscale. However, not all aspects are also fully understood from a metrological point of view. For the determination of mechanical properties of thin films the penetration depth must be as low as possible so that the deformation zone does not exceed the film. However, for small depths the results may be significantly distorted by the roughness of the thin film. The contact area is one of the crucial quantities involved and the most prone to errors. Since it cannot be measured directly in the experiment, it is usually determined independently either measuring directly the shape of the tip or using a known sample. However, there may be discrepancies between the contact areas for different setups. Instruments often just assume the sample to be perfectly flat and a perfect alignment of the sample and the indenter tip axis. Obviously roughness or a tilt of the surface can change the contact area and represent a significant source of uncertainty, especially for small depths. Experimental data will be used to simulate the change of contact area on a rough sample using the finite element method (FEM) and Monte Carlo methods. Results will be compared to theoretical models.
Authors : D. Eisenhauer 1, B. Pollakowski 2, J. Baumann 3, V. Preidel 1, D. Amkreutz 4, B. Rech 4, F. Back 5, E. Rudigier-Voigt 5, B. Beckhoff 2, B. Kanngießer 3, C. Becker 1
Affiliations : 1: Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Young Investigator Group Nanostructured Silicon for photovoltaic and photonic implementations (Nano-SIPPE), Kekuléstr. 5, 12489 Berlin, Germany; 2: Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin, Germany; 3: Technische Universität Berlin, Institut für Optik und Atomare Physik, Analytische Röntgenphysik, Hardenbergstr. 36, 10623 Berlin, Germany; 4: Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Institut Silizium-Photovoltaik, Kekuléstr. 5, 12489 Berlin, Germany; 5: SCHOTT AG, Hattenbergstr. 10, 55122 Mainz, Germany
Resume : Crystalline silicon thin-film solar cells on glass fabricated by liquid-phase crystallization enable an excellent electronic material quality providing open-circuit voltages up to 600 mV. Periodic nanostructuring of the substrate by nanoimprint-lithography efficiently increases the absorption in the thin silicon layer. Due to the high temperatures applied during crystallization (T > 1414°C), the consistency of the nanopatterned interface between substrate and silicon, and the choice of appropriate interlayers is crucial for device performance. In this study, we performed grazing-incidence X-ray fluorescence (GIXRF) measurements at the electron-storage ring BESSY II for depth-dependent characterization of the buried substrate-silicon interface region. The interface of the silicon absorber was made accessible for GIXRF measurements by removing both the glass substrate and interlayers in concentrated hydrofluoric acid. GIXRF provides a non-destructive access to the depth distribution of the involved elements. In particular for nanopatterned structures the determination of these elemental profiles is challenging, as it is significantly influenced by the 3D interfacial structure. Calibrated instrumentation was used for the measurements allowing for a reference-free quantization. The contamination level in the absorber was found to be strongly influenced by the interlayers (silicon oxide, silicon carbide or a combination of both) - and correlates with respective solar cell results.
Authors : Z. Skanderi1*, F. Mechachti1, S. Bitam2, A. Djebaili1
Affiliations : 1 Laboratory of chemistry and environmental chemistry L.C.C.E - University of Batna- Algeria 2 Laboratory of Physical chemistry- University of Media- Algeria
Resume : In order to find an interpretation to the isomerization reaction of undoped 'cis ' polyacetylene PA, we have resumed the recent work and analyzed them using the most advanced methods. We used the line intensities attributed to deformation vibrations of C-H bonds out-of-plane at 740 cm-1 for cis and 1015 cm-1 for trans to calculate the ratio cis / trans. The relative percentages of the cis and trans are calculated by: % cis = 100 x 1,3 . A cis (740 cm-1) / 1,3 . Acis (740 cm-1) + Atrans(1015 cm-1 ) % trans = 100 x A trans (1015 cm-1) / 1,3 . Acis (740 cm-1) + Atrans(1015 cm-1 ) These two bands are close to each other, we used a program based on deconvolution, in order to resolve these peaks: LineSim simulation program written by P.F. Barron from Brisbane NMR Centre, Griffith University, Natman Q 4111, Australia. The results of the rate of cis and trans isomers obtained by NMR were compared with those given by FTIR. We observed that for high levels of cis, values calculated by NMR are always higher than those given by infrared, while this trend is reversed at high levels in trans. The results of this study are presented in the following table: Ito1 F.T.I.R Gibson2 R.M.N Montaner3 F.T.I.R Tabacik4-5 Raman - DSC Energy Ea ( cal / mole ) 17181.295 12840.102 30524.790 31000.000 Collision factor A(s-1 ) 4.28 108 3.94 103 8.86 1012 2.27*1013 Temperature field (°C) 75 -- 115 90 -- 110 115 -- 160 120 -- 160 Regression coefficient r - 0.991113 - 0.946320 + 0.958370 + 0.999985
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Authors : Philipp Hönicke1, Matthias Müller1, Blanka Detlefs2, Claudia Fleischmann3, Beatrix Pollakowski1, Burkhard Beckhoff1
Affiliations : 1 Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin, Germany 2 CEA LETI, DTSI / SDEP, 17 rue des Martyrs, 38054 Grenoble, France 3 IMEC, Kapeldreef 75, B-3001 Leuven, Belgium
Resume : The accurate characterization of nanoscaled systems is an essential topic for todays developments in many fields of materials research. Thin high-κ layers and stacks as well as ultra-shallow dopant profiles are technologically relevant for current and future electronic devices. But the metrological challenges to characterize such systems require a further development of the current analytical techniques. When performing Grazing Incidence X-ray Fluorescence (GIXRF) analysis in combination with X-Ray Reflectometry (XRR), the characterization reliability for such nanoscaled systems can be improved. GIXRF is based on the incident angle induced changes of the X-ray Standing Wave (XSW) field intensity profile. The combination with XRR allows for a more reliable modeling of the XSW. Employing in-house built instrumentation  and radiometrically calibrated detectors at the Physikalisch-Technische Bundesanstalt the combined method allows for reference-free quantitative in depth analysis [2,3]. The capabilities of the XRR enhanced GIXRF method are demonstrated by means of several nanoscaled layer systems, ultra-shallow dopant profiles and self-assembled molecular samples. The results are validated by complementary investigation.  J. Lubeck et al., Rev. Sci. Instrum. (2013) 84, 045106.  P. Hönicke et al., J. Anal. At. Spectrom. (2012) 27, 1432-1438.  P. Hönicke, M. Müller, B. Beckhoff, Solid State Phenomena (2013) 195, 274-276.
Authors : Diane Eichert, Werner Jark, Lars Luehl, Alessandro Gambitta, Andreas Germanos Karydas, Alessandro Migliori, Juan Jose Leani, Mladen Bogovac, Halim Sghaier, Ralf Bernd Kaiser
Affiliations : Diane Eichert - X-Ray Fluorescence Beamline - ELETTRA - Sincrotrone Trieste, Area Science Park, 34149 Basovizza, Trieste, Italy; Werner Jark -X-Ray Fluorescence Beamline - ELETTRA - Sincrotrone Trieste, Area Science Park, 34149 Basovizza, Trieste, Italy; Lars Luehl - X-Ray Fluorescence Beamline - ELETTRA - Sincrotrone Trieste, Area Science Park, 34149 Basovizza, Trieste, Italy; Alessandro Gambitta - X-Ray Fluorescence Beamline - ELETTRA - Sincrotrone Trieste, Area Science Park, 34149 Basovizza, Trieste, Italy; Andreas Germanos Karydas - International Atomic Energy Agency, Nuclear Science and Instrumentation Laboratory, Seibersdorf, Austria; Alessandro Migliori - International Atomic Energy Agency, Nuclear Science and Instrumentation Laboratory, Seibersdorf, Austria; Juan Jose Leani - International Atomic Energy Agency, Nuclear Science and Instrumentation Laboratory, Seibersdorf, Austria; Mladen Bogovac - International Atomic Energy Agency, Nuclear Science and Instrumentation Laboratory, Seibersdorf, Austria; Halim Sghaier - International Atomic Energy Agency, Nuclear Science and Instrumentation Laboratory, Seibersdorf, Austria; Ralf Bernd Kaiser - International Atomic Energy Agency, Nuclear Science and Instrumentation Laboratory, Seibersdorf, Austria
Resume : The XRF beamline is conceived as a multi-purpose beamline designed to accommodate a variety of end-stations dedicated to e.g. microscopy, Total Reflection XRF (TXRF) or spectroscopy. The XRF beamline is located at a bending magnet source. Its excitation energy range is 2-14 keV, its resolving power 1.4 10-4. The source is re-imaged to a 250 X 50 mm beamsize (hor X vert) in an exit slit, with an angular divergence of 0.15 mrad and a transmitted flux of about 5 109 ph/s (5.5 keV, 2GeV). The XRF beamline is presently hosting the IAEA Ultra-High-Vacuum Chamber (UHVC), based on a prototype built by PTB , currently under commissioning. The aim is using tunable synchrotron X-rays with 50 m beamsize for various X-Ray Spectrometry techniques: TXRF, Grazing Incidence/Exit XRF (GI-XRF/GE-XRF), X-Ray Reflectometry (XRR) or X-ray Absorption Spectroscopy (XAS). GIXRF is an established tool for the elemental analysis of nanoscaled materials surfaces or interfaces. Combined with XRR it provides relevant insights into nanoscaled layered systems, and correlated with XAS can probe elemental speciation. This addresses well characterization issues in the nanometer range of energy-related nano-scaled materials. A description of the beamline, analytical developments, commissioning results and pilot research experiments will be presented, and highlights put on the manifold possibilities that the setup offers to analyse nanoscale samples.  J. Lubeck et al (2013) Rev. Sci. Instrum. 84: 045106
Advances in thermal characterisation of thin films and nanomaterials : Bruno Hay and Petr Klapetek
Authors : S. Gomés, S. Lefévre, P.-O. Chapuis
Affiliations : Université de Lyon, CNRS INSA-Lyon, CETHIL, UMR5008, F- 69621, Villeurbanne, France Université Lyon 1, CETHIL, UMR5008, F-69621 Villeurbanne cedex, France
Resume : Although significant progress has been made for managing heat transfer at small scales, much remains to be understood about heat flow in nanostructures. At the extreme length scales under consideration, the macroscopic physical laws and models fail. The required investigations will not be possible without the development of new thermal measurement techniques since classical thermal metrology methods are limited in resolutions. Various methods with high spatial and temporal resolutions have been developed in the last twenty years. The more confirmed ones are based on optical or photothermal techniques. While lateral spatial resolution of these optical techniques is limited by diffraction, Scanning Thermal Microscopy (SThM) is promising since its spatial resolution depends on the characteristic length of the predominant physical mechanism operating at the nanometric contact between the probe and the sample. After a review of the possibilities of the techniques proposed by various groups, an overview of the results achieved by our group since more than 10 years will be presented. The discussion will mainly focus on application of scanning thermal microscopy for the characterization of thermophysical properties of nanostructured materials from various application areas such as microelectronics and polymer sciences.This will highlight the challenges to be tackled to succeed in realizing Nanoscale Quantitative Thermal Analyses and Thermal Measurements by SThM.
Authors : A.F. Lopeandia#&; M. Molina-Ruiz#; G.García#; O.Bourgeouis&; J.Rodriguez-Viejo#;
Affiliations : # Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain. & Institut NEEL CNRS/UJF, 38042 Grenoble cedex 9, France
Resume : The use of membrane-based chip calorimeters has opened the way of studying size dependence of thermodynamic properties in nanomaterials. Among the different calorimetric methods implemented for chip, quasi-adiabatic nanocalorimetry  reports the better sensitivity per unit area, but do not offers the possibility of measuring heat capacity at constant temperatures as function other variables (time, magnetic field ) like ac-calorimetry . We present a new operational method combining the better characteristics of both methods previously mentioned. In this method, the calorimetric cell, consisting of a silicon nitride membrane (~180nm thick) and a thin film metallic sensor, is heated by joule effect with train of current pulses (few us width, ms separated) promoting local temperature scans that span few K over the base temperature. The possibility of multiple scan averaging and the huge heating rates accessible (up to 10^6 K/s) permits to reach exceptional heat capacity resolution of 100 pJ/mmK√Hz. The method is demonstrated characterizing the antiferromagnetic transition in CoO thin film samples of 5 and 10 nm thick.  S.L.Lai et al., Appl.Phys.Lett. 67 (9), p1229 (1995)  P.F. Sullivan et al., Phys. Rev., 173 (3), p679 (1968)
Authors : Nolwenn Fleurence, Bruno Hay, Guillaume Davée, Andréa Cappella
Affiliations : Laboratoire national de métrologie et d'essais
Resume : Industrials are constantly innovating in the field of thin films due to the continued drive towards miniaturization. As an example, to replace old floating gate technology producers are working on a new generation of non-volatile memory based on phase change materials, typically chalcogenide materials. The phase change temperatures (amorphous and crystalline phases) of these type of alloys may reach several hundred degrees. These specific operating environments (nanoscale and high temperature) require accurate knowledge of the thermal characteristics of the materials under conditions of use. The understanding of the thermal behaviour of thin films is essential to improve for example the performances of these new generations of phase change memories (PCMs), by increasing storage density, access speed and reliability. This paper presents the thermal conductivity measurements of phase change chalcogenide thin films versus temperature and crystalline structure. These measurements were performed by using a modulated photothermal radiometry apparatus developed at LNE for accurate knowledge of thermal properties of thin films under their specific operating conditions. At the same time, the thermal resistance at the thin film / substrate interface was also evaluated. This work was funded through the European Metrology Research Programme (EMRP) Project IND07 Thin Films. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union.
Authors : Ah.Dhahri. E.Dhahri and E. K. Hlil
Affiliations : Ah Dhahri, E Dhahri : Applied Physics Lab, Faculty of Sciences Sfax, BP 1171, University of Sfax, 3000, Tunisia. E K Hlil : Institut Néel, CNRS, MCBT Department, BP 166, 38042 Grenoble Cedex 9, France
Resume : We have studied the effect of Cr substitution on structural, magnetic and magnetocaloric properties in La0.7Sr0.16Ca0.17Mn1-xCrxO3 (x = 0, 0.05, 0.1, 0.15 and 0.2) manganite. The X-ray diffraction studies show that all samples crystallize with the orthorhombic symmetry within the space group Pnma (No 62). Rietveld refinement shows that the chromium modify the structural parameters such as the volume, the Mn-O-Mn angles and the Mn-O bond length. All samples undergo a transition from paramagnetic(PM) to ferromagnetic(FM) phase at the Curie temperature, Tc which decreases from 295K down to 225K with increase in the Cr doping level from x= 0 to x= 0.2. Around TC, the magnetic entropy change (-Sm) was estimated from isothermal magnetization curves and it decreases with increase of Cr content from 6.20J.kg-1.K-1 at 295K(x =0) to 2.45 J.kg-1.K-1 at 225K(x=0.2) under µ0H=5T and the relative cooling power (RCP) approached 240 and 178.115 J.kg-1for Cr doped materials in the magnetic change of 5T. The obtained results suggest that Mn-site Cr dopant actually disfavors the enhancement of the magnetocaloric effect in some perovskite manganites due to a weakening of the ferromagnetic double-exchange interaction between Mn3+ and Mn4+ ions of the original atomic structure.
Authors : Agnès Tempez,Emmanuel Nolot,Sébastien Legendre,Jean-Paul Barnes,Fabrice Nemouchi, Cécile Maunoury
Affiliations : Horiba Jobin Yvon, CEA LETI
Resume : Plasma Profiling Time of Flight Mass Spectrometry (PP-TOFMS) provides direct measurement of the elemental composition of materials as a function of depth, with nanometre resolution and the capability to measure both thin and thick layers . It consists in a pulsed radio frequency glow discharge plasma source fed with pure Ar and created under a pulsed RF potential coupled to a time of flight mass spectrometer (TOFMS). The ultra-fast detection and quasi-simultaneous acquisition of all mass ions of the TOFMS fits well with the fast erosion rate of the high density and low energy plasma source. Furthermore the separation between sputtering and ionisation processes makes this technique much less matrix dependent compared to SIMS. In addition, the orthogonal TOFMS configuration allows for temporal monitoring of the transient signals generated in the pulsed plasma. This is all the more important as signals are largely enhanced in the plasma extinction phase (once RF is turned off) in the so-called afterglow region. Ion signals are then generated through Penning Ionisation by Ar metastables. Various examples in microelectronics and nanotechnology will be presented such as magnetic layers for 3D sensors, Pt-doped Ni-silicides for advanced contacts, and TiN layers for CMOS. It will be shown that PP-TOFMS allows for determining composition, detecting contamination, measuring doping level, and characterising diffusion mechanisms. Results will be compared to other techniques (XRF, SIMS, and XRR) and aspects of analytical performance with regards to sensitivity, quantification, repeatability and sample throughput will be discussed.  R. Valledor et al, Analytical and Bioanalytical Chemistry, 396, 2881-2887 (2010).
Authors : J.L.Colaux, C.Jeynes
Affiliations : University of Surrey Ion Beam Centre, Guildford, England
Resume : MeV IBA uses light ion scanning microbeams to non-destructively probe materials in 3D down to 10 microns depth and more, exciting both (atomic) particle-induced X-ray emission (PIXE) and (nuclear) elastic backscattering (EBS) a special case of which is Rutherford backscattering spectrometry (RBS). The high depth resolution of IBA comes from the inelastic energy loss processes that dominate nuclear spectrometry and are responsible for PIXE. Advances recently reviewed [Nucl. Instr. Methods B, 271 (2012) 107] have allowed spectra from both atomic and nuclear excitations to be handled self-consistently, meaning that X-ray data from layered materials whose layer structure is unknown can be interpreted fully quantitatively. PIXE and EBS are always both available, and are strictly complementary: where one is strong the other is weak (PIXE: mass and trace sensitivity; EBS: accuracy and depth). Fully quantitative analysis of completely blind samples is now feasible [Nature Geoscience 6, (2013) 1018]. Recently, we have demonstrated a class of samples for which the quantity of material can be determined by RBS with a traceable absolute accuracy of 1% [Anal.Chem.84 (2012) 6061; Anal.Meth.6 (2014) 120], an accuracy unprecedented for standard-less and model-free non-destructive analysis of thin film samples. We will discuss the applicability of these methods for wider classes of samples, and also discuss how PIXE inherits the accuracy of backscattering spectrometry.
Authors : Andreas Hertwig, Dana Rosu, Uwe Beck, Luca Croin, Giulia Aprile, Luca Boarino
Affiliations : BAM - Federal Institute for Materials Research, Germany; BAM - Federal Institute for Materials Research, Germany; BAM - Federal Institute for Materials Research, Germany; INRIM - Istituto Nazionale di Ricerca Metrologica, Italy; INRIM - Istituto Nazionale di Ricerca Metrologica, Italy; INRIM - Istituto Nazionale di Ricerca Metrologica, Italy
Resume : Ellipsometry is a valuable non-destructive tool for measuring the properties of thin films in optoelectronic systems. Apart from simple stratified transparent layer systems, micro and nanocomposite systems have been investigated in recent years following important improvements in ellipsometric analysis algorithms, layer models, and software tools. In this work, a study on polystyrene nanospheres and other nanoscale structures distributed on a silicon surface is presented. These systems are intended to be models in a strategy to develop analysis methods for composite organic materials. These materials are widely used in optoelectronic applications such as OLEDs and bulk organic photovoltaic systems. A combination of microscopic techniques and ellipsometry over a wide spectral range was used in this work to gain wide insight into the optical properties of the samples. The possible advantages as well as the limits of the ellipsometric measurement technique are discussed in this presentation.
Authors : Anh T.N. Dao, Derrick M. Mott, Shinya Maenosono
Affiliations : School of Materials Science, Japan Advanced Institute of Science and Technology
Resume : Plasmonic-based sensing probes consisting of nanoparticles (NPs) have become highly desirable because of their enhanced sensitivity, low cost, and easy to use nature. Silver is the most common type of metal studied for NP-based sensors because of their strong surface plasmon resonance (SPR) properties and especially intriguing because it has the highest optical cross section for any metal, but still suffers from oxidation and an inability of its plasmonic properties to be tuned for a desired application. Electronic charge transfer effect in multi-metallic system has been found to have ability to modify characteristic of metals such as chemical stability, plasmonic property, etc. In our research, Pt@Ag core@shell NPs with controllable size and shell thickness are synthesized and characterized by UV-Vis, XRD, TEM, HR-TEM, EDS, HAADF-STEM, and Raman spectroscopy. Especially, systematical and precise analysis using X-ray photoelectron spectroscopy reveal that these NPs display unique electronic properties where the silver shell gains electron density from the platinum cores which can enhance stability of Ag site. In addition, the plasmonic properties and unique electronic structure of this system can give us a wide avenue for future catalytic, SERS and other applications.
Authors : R. Unterumsberger*1, M. Müller1 and B. Beckhoff1
Affiliations : 1 Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, 10587 Berlin, Germany
Resume : The chemical speciation of buried nanolayers is an important part of the material analysis. Here, this was achieved by efficient soft X-ray Emission Spectrometry (XES). An increased sensitivity was achieved by focusing monochromatized soft X-ray undulator radiation down to the micrometer range using a high quality single bounce monocapillary . For validation purposes, the beam profile has been well characterized by two complementary methods, the knife-edge method and the so-called wire method. The effective focusing highly increases the sensitivity of a Wavelength Dispersive Spectrometer (WDS)  allowing for the detection and analysis of nanoscaled materials by XES. The lower limits of detection could be reduced below 1 nm for titanium L alpha- and boron K alpha-fluorescence radiation. Due to the increased sensitivity of the WDS, the chemical speciation of different nanoscaled titanium compounds was achieved. The measurements were carried out at the plane-grating monochromator beamline in the laboratory of the Physikalisch-Technische Bundesanstalt at the synchrotron radiation facility BESSY II using monochromatized undulator radiation and calibrated instrumentation [3,4]. References  R. Unterumsberger et al., Spectrochimica Acta Part B 78 (2012) 3741  M. Müller et al., Phys. Rev. A 79, 032503 (2009)  B. Beckhoff et al., Anal. Chem. 79, 7873 (2007)  B. Beckhoff, J. Anal. At. Spectrom. 23, 845 (2008) *corresponding author: email@example.com
Authors : Miroslav Valtr1, David Nečas2, Petr Klapetek1
Affiliations : 1 Department of Nanometrology, Czech Metrology Institute, Okruní 31, 638 00 Brno, Czech Republic; 2 Department of Physical Electronics, Faculty of Science, Masaryk University, Kotlářská 31, 611 37 Brno, Czech Republic
Resume : Thin films play a key role in our life. They can be used for example as wear-resistant protective coatings on cutting tools. Digital Imaging Spectrophotometry (also known as Imaging Reflectometry) is a fast non-contact technique that is often used for characterization of thin films. Although this technique is very fast, characterization of larger samples (> 10 cm2) would take enormous amount of time if it is possible at all. We designed a system with novel sample illumination set-up and a 2D stage for sample movement. The spectrophotometer can evaluate film thickness on area up to 113 x 136mm. It works in spectral range from 395 to 830nm and the lateral resolution in both axes is 18 um. The performance of the system will be demonstrated on a set of SiO2 thin films deposited on silicon substrate.
Authors : E. Axente1, J. Hermann2, G. Socol1, A. C. Galca3, D. Pantelica4, P. Ionescu4 and V. Craciun1*
Affiliations : 1Laser-Surface-Plasma Interactions Laboratory, Lasers Department, National Institute for Lasers, Plasma and Radiation Physics, RO - 077125, Măgurele-Bucharest, Romania 2LP3, CNRS - Aix-Marseille University, Luminy, Marseille, France 3Laboratory of Multifunctional Materials and Structures, National Institute of Materials Physics, RO - 077125, Măgurele-Bucharest, Romania 4 National Institute of Physics and Nuclear Engineering Horia Hulubei, RO - 077125, Măgurele- Bucharest, Romania
Resume : The use of amorphous and transparent semiconductor oxides (ASOs) is key for the development of new thin film transistors (TFTs), solar cells electrodes and displays. By controlling the stoichiometry ASOs can be used as TFT channel (semiconductive behavior) or as transparent electrode (conductive behavior). Recently, room temperature deposited indium zinc oxide (IZO) and indium gallium zinc oxide (IGZO) was shown to exhibit a very good transparency in the visible range, low resistivity, and high mobility. Since the optical and electrical properties of these films depend on the In/(In+Zn) and Ga/(Ga+Zn) values, the measurement of this ratios is important for future developments and applications. Here we focused on the relationship composition - properties of IZO and IGZO thin films synthesized using advanced Pulsed Laser Deposition technique. An accurate monitoring of the thin films elemental composition was performed by Laser-Induced Breakdown Spectroscopy (LIBS) based on plasma modeling in view of further in-situ and real-time technological developments and process control in case of ASOs fabrication. The cation fractions measured by LIBS were compared to values obtained by complementary measurements using Rutherford backscattering spectrometry. The optical properties (thickness profile and refractive index determination) of the thin films were inferred from spectroscopic ellipsometry. Complementary investigations have been performed by fitting the measured X-ray reflectivity curves with simulated ones using a dedicated model to obtain the thickness and density of the deposited films. The room temperature electrical properties were investigated using typical four-point probe geometry and Hall measurements.
Authors : C. Streeck 1, A. Nutsch 1, J. Weser 1, T. Fischer 2, P. Dietrich 2, K. Rurack 2, W. Unger 2 and B. Beckhoff 1
Affiliations : 1 Physikalisch-Technische Bundesanstalt (PTB), Abbestr.2-12, 10587 Berlin, Germany 2 Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
Resume : Functionalized surfaces are essential in biotechnology, e.g., for the development of biosensors and microarrays. Knowledge of the quantity of primary reactive groups on such surfaces is indispensable for a defined secondary modification with commonly biochemical entities, eventually resulting in more reliably tailored surfaces with better controlled properties. Here, we investigated aminated glass surfaces with varying densities of amino groups prepared from binary mixtures of silanes. Subsequent labeling of the amino groups with a fluorophore containing a high number of fluorine atoms allows complementary quantification of the organic groups by optical fluorescence spectroscopy, X-ray Photoelectron Spectroscopy (XPS) and traceable Total-Reflection X-ray Fluorescence analysis (TXRF). Reference-free TXRF with soft X-ray excitation determines the mass deposition of elements such as carbon, nitrogen and fluorine, yielding the areal density of primary functional groups and fluorophore on the surface. The TXRF-measurements were performed at the PTB beamline for undulator radiation at the electron storage ring BESSY II which provides monochromatic soft X-rays with high spectral purity and photon flux. This approach allows the calibration of optical fluorescence spectroscopy and XPS to deliver traceable quantitative data.
Authors : K. BENOUMSAAD1*; ILHEM. R. KRIBA1; A. DJEBAILI2
Affiliations : 1 Plasma Laboratory - Faculty of Sciences Department of Physics- University of Batna- Algeria 2 Laboratory of chemistry and environmental chemistry L.C.C.E - University of Batna- Algeria,
Resume : The first originality of the experiments we carried out consists of the use of a laser beam as a double agent: simultaneously as activation agent inducing the isomerization reaction of the PA, and for the Raman diffusion. The laser beam power P (λ) is equivalent to the temperature T of isotherm i of isomerization reaction. The second originality consists of use of multichannel spectroscopy which enables the simultaneous observation of both reactants (PAcis) and product (PAtrans) in the same time, since PAcis absorption band and PAtrans absorption band are clearly shifted on a band of 512 diodes Then we have a double simultaneity (i) In one hand the heating and the diffusion of the laser beam, (ii) On the other hand the steady measurement of the concentrations. We elaborate a numerical model reproducing the Raman experiment within 5 % error. The rate constants, activation energy values, Arrhenius factors and linear regression coefficients are obtain with a small error. The kinetic results obtained, such as reaction orders values obtained, varying from 1/2 to 2/3, showed clearly that, the isomerization reaction of undoped P.A. remains a complex process. The reaction order of 2/3 seems to be the most appropriate value in this case, since it refers to a solid state reaction propagation, where the reaction rate is controlled by a three dimensional development of active centers, in agreement with Sestak and Berggren theory
Authors : J. Lubeck1, I. Holfelder1, B. Beckhoff1, R. Fliegauf1, P. Hönicke1, M. Müller1, A. Nutsch1, P. Petrik2, F. Reinhardt3, G. Roeder4, B. Pollakowski1, J. Weser1
Affiliations : 1 Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin, Germany 2 Institute for Technical Physics & Materials Science (MFA), Research Centre for Natural Sciences, Konkoly Thege u. 29-33, 1121 Budapest, Hungary 3 Bruker Nano GmbH, Am Studio 2D, 12489 Berlin, Germany 4 Fraunhofer IISB, Schottkystraße 10, 91058 Erlangen, Germany
Resume : A versatile UHV instrument  enabling synchrotron radiation based X-Ray Spectrometry (XRS) related techniques for nanoanalytics and X-Ray Reflectometry (XRR) was developed by PTB. An integrated 9-axis manipulator allows for a reproducible sample alignment in all degrees of freedom. A translational and rotational movement of several photodiodes as well as a translational movement of a rigid aperture system which enables reference-free X-Ray Fluorescence (XRF) analysis is possible. By means of a flexible beam geometry from total reflection (TXRF), grazing incidence (GIXRF) to conventional XRS, including access to polarization-dependent detection channels as well as simultaneous XRR measurements, reliable information about layer thicknesses, elemental or spatial compositions, elemental depth profiles, chemical bonding states and the molecular orientation of bonds can be determined. In addition, the steadily increasing demand for the validation, assurance, and support involving various analytical methods is driving the integration of multiple methods into one tool for 450 mm Si wafers. Therefore, a design study for a 450 mm analytical platform  was performed, integrating several complementary methods into one tool, X-ray analytical methods such as TXRF, GIXRF, XRF, XRR, XRD and GISAXS as well as ellipsometry and vacuum UV reflectometry. References:  J. Lubeck et al., Rev. Sci. Instrum. 84, 045106 (2013)  I. Holfelder et al., J. Anal. At. Spectrom. 28(4), 549-557 (2013)
Authors : Yves Ménesguen, Bruno Boyer & Marie-Christine Lépy
Affiliations : CEA, LIST, Laboratoire National Henri Becquerel (LNE-LNHB), F-91191 Gif-sur-Yvette, France
Resume : Studying new materials requires new techniques. A lot of new materials developed either in public research institutes or private companies are created for their new functionalities and are very often deposited as layers in stacks. Some of their properties can be affected by bad or uncontrolled interfaces as well as roughness, inhomogeneity. Grazing incidence x-ray techniques are of major interest as they can give information about in-depth or interfaces properties of materials. In collaboration with PTB, the LNHB decided to build a GIXRF setup designed to do metrology studies about these new materials. PTB, pioneer in this field, defined the specifications of the manipulator in order to meet up-to-date performance in positioning samples, detectors to deliver the best possible results. We report here on the assessment of the setup, mechanical, electrical, vacuum and software engineering. Mechanical performances were tested at PTB and met their specifications. The final assembly was done by LNHB and PTB. The setup will be equipped with several diodes, some of them calibrated by LNHB using the BOLUX setup. 1) P. Troussel, N. Coron, BOLUX : A cryogenic electrical-substitution radiometer as high accuracy primary detector in the 150-11000 eV range, Nuclear Instruments and Methods in Physics Research A, 614 (2010) 260-270
Authors : Peter D. Tovee and Oleg V. Kolosov
Affiliations : Physics Department, Lancaster University, Lancaster, LA1 4YB, UK
Resume : Nanoscale thermal properties are becoming extremely importantfor modern chips that dissipate increasing current densities. While Scanning Thermal Microscopy (SThM) that uses locally heated nanoscale probes is known to probe thermal properties of materials with nanoscale resolution, until today it was perceived impossible to use active SThM in a liquid environment due to heat dissipation into the surrounding liquid that would deteriorate SThM and spatial resolution. Nonetheless, our recent theoretical analysis of immersion SThM (iSThM) showed that for a resistive heater located near the tip apex, the probes thermal signal is only moderately affected, on immersion in a dodecane environment, while spatial resolution is similar to in air SThM and the tip-sample thermal contact is beneficially improved. Our trials of iSThM were successful and here we report measurements of thermal conductivity of Ultra Large Scale Integration (ULSI) polymer-ceramic-metal interconnects and nanoscale graphene flakes immersed in liquid environment. The immersion directly thermally links the tip to the interconnect Al lead, allowing to avoid spurious presence of surface voids and roughness, while preserving thermal resolution down to 50 nm. iSThMopensa potentially broad range of applications from non-contact measurements of thermal transport in semiconductor devices to exploring catalytic reactions in liquid phase and heat generation in biological systems. Nanotechnology Vol. 24 (2013) 465706
Authors : D. Grötzsch1, W. Malzer1,B. Kanngießer1, C.Streeck2, A. Nutsch2, B.Beckhoff2, C. Nietzold3, P. Dietrich3, W. Unger3
Affiliations : 1 Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin 2 Physikalisch Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin 3 Bundesanstalt für Materialforschung und prüfung, Unter den Eichen 87, 12205 Berlin
Resume : Capturing biochemical markers by biomolecular films is one of the most promising approaches for the development of highly sensitive and highly selective diagnosis. In particular future innovative tools for in vitro or point of care diagnostics are expected to rely on this principle. Analytical techniques which can provide information on coverage, orientation and chemical state of biochemical films are capable of contributing to a purposeful development of such diagnostics. The liquid cell we present was designed to facilitate the application of soft X-ray spectrometry for the in-situ analysis of biomolecular films at solid-liquid interfaces. It allows for - the analysis through a silicon nitride window with a thickness of 150 nm - in situ preparation of successive layers by rinsing the window Currently, after the first successful soft X-ray experiments we are improving the versatility of the liquid cell. Spectrometry in transmission and in various emission geometries will be feasible. Further controls for the experimental conditions will be added.
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Authors : James C Blakesley , Fernando Castro, Alina Zoladek-Lemanczyk, Stephen Giblin, Alan Turnbull
Affiliations : National Physical Laboratory, Teddington, TW11 0LW, United Kingdom
Resume : Pc-AFM is a method with potential for imaging nanoscale features in photo-active thin films. It has the ability to image features that affect optoelectronic properties, even where these features are buried below the film surface. There is interest in applying the technique to the study of bulk heterojunction photovoltaics. Optimal photo-active layers comprise donor and acceptor phases intimately mixed on a < 10 nm scale. This mixing is too fine to be resolved by Pc AFM. However, defects in the morphology frequently occur on length scales of 10 1000 nm. These, being on a similar scale to the film thickness, can have a significant impact on the macroscopic device properties, while still being too small to identify with conventional optoelectronic methods. Pc-AFM has been used to image donor nanowires buried within an acceptor film . It has also been used to identify sub-surface acceptor aggregate defects . However, the interpretation of the high-resolution photocurrent images requires deep physical insight. We have developed a tool for simulating the processes of photocurrent generation and conduction under the AFM tip. We report on simulations of model photovoltaic systems and compare them to experiments. The tool is used to help interpret experimental results, and to determine the limitations of Pc-AFM as a instrument for imaging mesoscopic defects.  Tsoi et al., Energy & Environ. Sci. 4, 3646 (2011)  Coffey and Ginger, Nat. Mater. 5, 735 (2006)
Authors : Petr Klapetek, Miroslav Valtr
Affiliations : Czech Metrology Institute, Okuzni 31, 638 00 Brno, Czech Republic
Resume : Photoconductive atomic force microscopy is a technique allowing us to map local charge generation on samples exposed to an illumination. In most cases this is done by conventional atomic force microscope equiped with additional source of illumination, conductive probe and very sensitive transimpedance amplifier. This techniques is particularly useful while studying local structure and functionality of solar cell materials. To estimate from which area the signal was collected is however not straightforward as the probe sample geometry is quite complex and light scatters in many ways while illuminating the sample. In this contribution we present computational approach to address the issues of light localisation, measurement resolution and measurement uncertainty in conductive AFM, using Finite Difference in Time Domain method for optical calculations and Finite Element method for electrical calculations. We will discuss effects of overall sample morphology, presence of thin films and nanoscale roughness, using realistic data including all these imperfections as model input and comparing outputs to experimental results.
Authors : Alexandra DELVALLEE, Nicolas FELTIN, S?bastien DUCOURTIEUX
Affiliations : Laboratoire National de m?trologie et d?Essais ? LNE, 29 avenue Roger Hennequin, 78197 Trappes Cedex
Resume : The LNE?s nanometrology team develops a platform dedicated to the metrological characterization of nanomaterials (CARMEN) and more specifically to the metrology of the mean diameter and size distribution of a population of spherical nanoparticles (NPs) by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). The objective is to ensure the traceability of the measurements to the International System of Units and to be able to compare it. To determine the diameter of NPs by AFM, and due to the tip/surface dilation that leads to a broadening of the lateral measurement, we developed a method based on the measurement of NPs height with a expanded uncertainty of 0.8 nm for particles of 50 nm. On the contrary of AFM, the SEM is unable to give quantified information along Z axis. That is why the lateral diameter measurement is adopted for the size measurements of NPs. A partial uncertainty budget is given. A two step method has been developed for AFM and SEM image processing. The first step is realized with a commercial software and consists in levelling and binarizing images. The second is realized with a home-made software and consists in detecting, measuring and drawing NPs distribution. To compare both methods, a 80 nm SiO2 NP population was deposited on a silicate substrate. Measurement comparison was done from 1 SEM and 4 AFM images. NPs distribution shows a leading mode at 85.5 nm for SEM image and 79.1 nm for AFM. One explanation for this observation is the fact that not the same NPs are observed by AFM and SEM. So, the LNE is investigating colocalization techniques to image exactly the same NPs by both instruments.
Authors : Tsvetelina Gerganova a, Gert Roebben a, Vikram Kestens a, Yannic Ramaye a, Thomas Linsinger a, Andrea Held a, Eveline Veleysen b, Jan Mast b, Hendrik Emons a
Affiliations : a) European Commission, Joint Research Centre, Institute for Reference Materials and Measurements (IRMM), Retieseweg 111, 2440 Geel, Belgium b) Veterinary and Agrochemical Research Centre (CODA-CERVA), Service Electron Microscopy, Groeselenberg 99, 1180 Brussels, Belgium
Resume : Manufactured nanomaterials are an important product of nanotechnology, and enable innovations in many other technology sectors. In order to better understand and use these materials, an increasing number of measurement methods are being used to characterise nanoscale objects. The measurements in the nanometer range are challenging, and their limited accuracy may lead to disputes between suppliers and users of the material, or between producers and regulators. To be better comparable, the nanoscale measurement results should be traceable to internationally accepted units of measurement which requires common, validated measurement methods and calibrated scientific instrumentation. An important tool for instrument calibration, method validation and method verification are reference materials, i.e. materials with known (where possible certified) specified properties. Most of the available nanoparticle-based reference materials are developed for use in nanoparticle size analysis. But there is also a significant need for reference materials for nanoparticle shape analysis. Aspect ratio is well known as critical shape parameter which together with the minimum and maximum Feret diameter is influencing functional properties of nanomaterials. Progress in this field depends on a reliable assessment of nanoparticle shape, which can be improved by the development of appropriate reference materials. We illustrate here main criteria for the selection of suitable candidate reference materials for nanoparticle shape measurements and their further characterization.
Authors : Yezhou Shi, Paul F. Ndione, Linda Y. Lim, Dimosthenis Sokaras, Tsu-Chien Weng, Arpun R. Nagaraja, Andreas G. Karydas, John D. Perkins, Thomas O. Mason, David S. Ginley, and Michael F. Toney
Affiliations : 1. SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (USA) 2. National Renewable Energy Laboratory, Golden, CO 80401 (USA) 3. Northwestern University, Evanston, IL 60208 (USA) 4. NCSR Demokritos, Institute of Nuclear Physics,GR-15310, Athens (Greece) 5. Nuclear Spectrometry and Applications Laboratory, IAEA Laboratories, Austria A-2444 Seibersdorf (Austria)
Resume : The accurate quantification of defects in nanomaterials is essential to understand their functional properties. We describe the combined use of resonant X-ray diffraction (REXD) and X-ray spectroscopies to precisely determine anti-site defect concentrations in functional Ga2ZnO4 and Cr2MnO4 spinel oxide thin films. Cation lattice site swapping (e.g., tetrahedral (Td) cations occupying octahedral (Oh) sites) creates these defects and gives rise to self doping, which can result in charge carriers (holes) and modest conductivities. REXD probes structural and chemical information and quantifies lattice site-specific cation occupancies and oxidation states quantities difficult to study with conventional XRD. The REXD is complemented with X-ray absorption and emission spectroscopies (overall oxidation states), which are in good agreement with the REXD. For stoichiometric Ga2ZnO4 films, we find the anti-site defects are equal in concentration and electrically compensate each other. But for non-stoichiometric Cr2MnO4, excess Mn on the Td sites becomes electrically inactive as the Mn species switch from (III) to (II), resulting in an insulating film. This quantitative approach enables us to gain a better understanding of the nature of the anti-site defects and how they affect the electrical behavior of functional materials.
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Authors : E.Capria 1, J.Beaucour 2, R.Kluender 3, E.Mitchell 1, J.C.Royer 3, J.Segura-Ruiz 2
Affiliations : 1 European Synchrotron Radiation Facility - Grenoble (France), 2 Institut Laue Langevin - Grenoble (France), 3 LETI - Grenoble (France).
Resume : There is an increasing realisation worldwide that large-scale research infrastructures are a key component, not only of academic and fundamental research, but also of the innovation cycle and industrial research and development of micro- and nano-electronic devices and systems. However, working with industry has its own special requirements and research infrastructures are often based on an academic modus operandi which can limit their industrial impact. The IRT Nanoelec, is public-private partnership which comprises 18 public- and private-sector research partners - including the CEA-LETI (Laboratoire d'?lectronique des technologies de l'information), the ESRF (European Synchrotron Radiation Facility) and ILL (Institut Laue-Langevin). This platform, being created as a pathfinder project, it is focused on a core technology programme encompassing 3D assembly integration, nanophotonics on silicon and via technologies. This talk will depict the first results from this programme of industrial characterisation. Apart from the presentation of the main scientific results, emphasis will be given to the opportunities, limitations and viability of these characterisations, putting them into their economic context, driven by the industrial needs, and the valorisation of the products throughout their value chain. Finally, the perspectives for future developments, coherent with the electronic technology roadmaps and the actual main trends will be given.
Authors : Yves Ménesguen, Bruno Boyer & Marie-Christine Lépy
Affiliations : CEA, LIST, Laboratoire National Henri Becquerel (LNE-LNHB), F-91191 Gif-sur-Yvette, France
Resume : Reference-free analysis based on X-ray fluorescence (XRF) can be used to characterize innovative materials in terms of impurity checking, depth profiling or interfaces structure. Nevertheless, this technique requires accurate knowledge of the atomic parameters characterizing photon-material interactions, such as attenuation coefficients, fluorescence yields and transition probabilities. Tabulated parameters are available; however, experimental data are scarce with high associated uncertainties, especially in the low-energy range (E < 30 keV). New measurements using monochromatic radiation from the Metrology beam line of the SOLEIL synchrotron facility have been carried out to determine mass attenuation coefficients with relative uncertainties around 1 % for several materials . Fluorescence yields have also been measured using dedicated experimental setup and previously determined mass attenuation coefficients . New experimental data will be presented and made available for users on the LNHB web site. This improved knowledge of the fundamental parameters will allow developing more accurate XRF characterization techniques.  Y. Ménesguen and M.-C. Lépy, X-Ray Spectrometry 40 (2011) 411-416.  J. M. Sampaio, T. I. Madeira, J. P. Marques, F. Parente, A. M. Costa, P. Indelicato, J. P. Santos, M.-C. Lépy and Y. Ménesguen, Physical Review A 89, 012512 (2014).
Authors : C. Streeck 1, C. Herzog 2, B. Kanngießer 2, B. Beckhoff 1
Affiliations : 1 Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin 2 Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin
Resume : Synchrotron-radiation based Grazing Incidence X-ray Fluorescence analysis (GIXRF) with varying excitation angles provides non-destructive access to the compositional depth profile of thin film matrix elements in the nano- and micrometer range. Reference-free GIXRF in conjunction with fundamental parameter based quantification allows for an analysis without the need for any calibration standards. This XRF-methodology can be used e.g. for the non-preparative determination of elemental depth gradients with an In to Ga gradient in Cu(In,Ga)Se2 thin film solar cell absorber layers. As a key metrological aspect, the uncertainty of the components of the effective solid angle of detection and its impact on the uncertainty of the detected count rate will be presented: with varying angle of incidence the irradiated area on the sample changes over two order of magnitude, the Gaussian shape of the beam leads to an intensity distribution and the field of view of the detector is dependent on the distance from the sample. The uncertainty of all components shows a different angle dependency. Therefore, a detailed uncertainty analysis and their implication is prerequisite for a reliable calibration procedure.
Authors : D.M. Rosu1, A. Hertwig1, P. Petrik2, U. Beck1
Affiliations : 1BAM -Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12200 Berlin, Germany; 2Research Centre for Natural Sciences Institute for Technical Physics and Materials Science, Konkoly Thege Rd. 29-33, 1121 Budapest, Hungary
Resume : Consistent product quality is one of the main concerns nowadays in semiconductor industry and microelectronics. Therefore the development of techniques able to detect and inspect variations, defects and contaminations of devices is essential. A set of real-world samples with various non-idealities (thickness inhomogeneity, structured surface, non-stoichiometry) will be presented in the current work. These samples cover a range of materials relevant for semiconductor industry such as photoresist, structured silicon oxide thin layers, unusually thick silicon oxide layers, and silicon nitride. Spectroscopic ellipsometry in the visible range, mapping ellipsometry and IR spectroscopy were the investigation techniques used to obtain qualitative and quantitative information about our set of samples. The use of these ellipsometric methods is evaluated. Combined methodologies with e.g. X-ray measurement methods as complementary techniques are introduced. The discussion of these methodologies is focused on the possibilities for future development of reference samples and standard methods for calibrating optical surface measurement techniques.
Authors : Richard Koops, Petro Sonin, Omar El Gawhary
Affiliations : VSL, National Metrology Institute in the Netherlands Thijsseweg 11, 2629 JA Delft, the Netherlands
Resume : The characterisation of properties of materials through optical investigation means offers several appealing advantages compared to other competing techniques. First of all, at the common level of optical power used, such techniques are mostly not invasive and not destructive. Also, they are non-contact techniques which allows for a fast analysis of the sample of interest. Additionally, since electronic transitions in matter mainly fall in the visible range, the index of refraction of materials show a notable spectral diversity at optical frequencies, which increase the applicability of optical inspection methods and their sensitivity as well. In the last decades, ellipsometry and scatterometry have grown and developed in a way to become indispensable tools for the characterisation of physical properties of materials and their geometry. In this paper we will describe the design and realization of a compact polarization-encoded ellipsometer module that can be attached to a translation mechanism to expand the lateral measurement range up to meter level. The module is developed as part of the EMRP project IND07 ``Metrology for the manufacturing of thin films'' in order to implement traceable metrology tools for film thickness and refractive index measurements on large surfaces. Next to the actual realization and implementation, we will describe the modelling and the method used to retrieve the targeted material properties.
Authors : F. Manoocheri, S. Pourjamal, H. Mäntynen, P. Jaanson, E. Ikonen
Affiliations : Metrology Research Institute, Aalto University, P.O. Box 13000, FI-00076 Aalto, Finland
Resume : In this contribution, we present the characterization methods and the instrumentation for obtaining experimental results for the optical parameters and thickness profile of SiO2 thin-ﬁlm samples. These results are based on spectral reﬂectance data at multiple sample spots and angles of incidence including 10, 30, and 56.4 degrees. The optical parameters of the SiO2 coatings derived from the reﬂectance results at various spots are compared with those determined from the near-normal and oblique incidence of the central spot of the samples. Preliminary results indicate that the characterizations are consistent and agree within 0.9 nm and 17 nm for the nominal film thicknesses of 300 and 6000 nm, respectively. The consistency among the determined optical parameters of the thin-ﬁlm layers using a purpose-built gonioreflectometer and a commercial spectrophotometer used for these characterizations also conﬁrms the accuracy of the spectrophotometric measurements. The effect of the systematic factors in the measurements is also discussed. The analysis of the determined refractive indices for each set of the reﬂectance data did not reveal any reasonable absorption in the SiO2 layer. The physical thicknesses of the layer derived from the oblique-incidence spectrophotometric data for several spots are compared. As in the case of the refractive indices, both physical and optical thicknesses yielded by the reﬂectance data agree within 0.9 nm.
Highlights of European Metrology Research (EMRP) Programme Projects 3 : Fernando Araujo de Castro and Wolfgang Unger
Authors : R. Unterumsberger1, B. Pollakowski1, Christiane Becker2, Marcel Pagels3, Carolin Zachäus2 , Birgit Kanngießer3, B. Beckhoff1, Bernd Rech2
Affiliations : 1 Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin, Germany 2 Helmholtz-Zentrum für Materialien und Energie, Institut Silizium Photovoltaik, Kekuléstr. 5, 12489 Berlin, Germany 3 Technische Universität Berlin, Institut für Optik und Atomare Physik, Analytische Röntgenphysik, Hardenbergstr. 36, 10623 Berlin, Germany
Resume : The development of improved characteristics of functional nanoscaled devices involves novel materials, more complex structures and advanced technological processes, requiring analytical methods to be well adapted to the nanoscale. Thus, non-destructive and non-preparative techniques for chemical nanometrology providing sufficient sensitivity, reliable quantification and high information depth dynamics to reveal interfacial properties are needed for an interfacial analysis. Appropriate measurement strategies adapted to a nanoscaled stratified sample enables the combined technique of Near-Edge X-ray Absorption Fine Structure (NEXAFS) and Grazing Incidence X-ray Fluorescence (GIXRF) to provide interfacial species information. GIXRF-NEXAFS is a non-destructive and non-preparative technique which has the advantage that the interfacial chemical bonds remain unchanged by the measurement . By means of two examples the methodology will demonstrated. In particular high-temperature processed polycrystalline silicon thin-film solar cells were analyzed focusing on the interface between absorber and the transparent conductive oxide material . A reliable depth-resolving analysis of the elemental composition and chemical species close to the poly-Si/(SiN)/ZnO:Al interface was carried out by using the combined method GIXRF-NEXAFS. References:  B. Pollakowski et al., Anal. Chem. 85, 193 (2013),  Ch. Becker et. al., J. Appl. Phys. 113, 044519 (2013)
Authors : P. Petrik1, B. Pollakowski2, S. Zakel4, A. Nutsch3, G. Roeder4, T. Gumprecht4, B. Fodor1,5, E. Agocs, G. Juhasz1, O. Polgar1, C. Major1, Z. Labadi1, Z. Baji1, M. P. M. Jank4, M. Schellenberger4, B. Beckhoff2, M. Fried1
Affiliations : 1Institute for Technical Physics & Materials Science (MFA), Research Centre for Natural Sciences, Konkoly Thege u. 29-33, 1121 Budapest, Hungary 2Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany 3Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, D-38116 Braunschweig, Germany 4Fraunhofer Institute for Integrated Systems and Device Technology IISB, Schottkystrasse 10, 91058 Erlangen, Germany 5Faculty of Science, University of Pécs, 7624 Pécs, Ifjúság útja 6, Hungary
Resume : With shrinking device dimensions and layer thicknesses, there is an increasing need for the accurate measurement of thin and ultrathin films in a broad range of key technologies including biology, semiconductor device technology, photonics, photovoltaics, and sensor technology. The major challenge of optical ultrathin film metrology is the appropriatemodeling of interfaces, as well as of potential lateral and vertical layer inhomogeneity of the optical properties. For the determination and interpretation of optical properties of layers with thicknesses of several nanometers, even surface structures or interface roughness at nanometer scale play a crucial role. The way the interfaces are modeled also influences the determined bulk optical properties of the thin films to a large extent. Organic surface contamination has been revealed by vacuum ultraviolet reflectometry. Lateral inhomogeneity is a major concern whenever a comparative study is preformed involving different methods. For a reliable study, the lateral homogeneity has to be carefully checked and taken into account. The vertical inhomogeneity of the layer has a similar importance in comparative measurements if the information depths of the applied methods are different. A further problem with ultrathin films is that their optical properties are different from bulk values, and their dispersion needs to be modeled. We show for the example of ZnO that modeling of the dielectric function is a complex task, especially for photon energies around the band gap and at critical points. Around the critical point energies, the penetration depth of light strongly depends on the wavelength, which allows a depth scan by changing the wavelength, but also sets limitations in terms of film thickness, and requires proper modeling of the vertical inhomogeneity.
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Authors : B. Pollakowski, J. Eilbracht, B. Beckhoff
Affiliations : Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin, Germany
Resume : Many functional nanoscaled devices have a complex structure consisting of several thin layers. For a quantitative analysis of the elemental composition of this kind of specimens X-ray spectrometry under grazing incidence conditions is a beneficial method. Under these conditions interference effects of the incoming and the reflected radiation occur at smooth interfaces of stratified materials. The related spatial intensity distribution has a nanoscaled periodicity and is named the X-ray Standing Wave (XSW) field. The mean penetration depth can be tuned to a buried nanostructure of interest. The information depth follows the penetration depth that can be adapted by changing either the angle of incidence or the photon energy. The information depth can vary from a few to several hundreds of nanometers. Quantitative GIXRF leads to most reliable results when the actual XSW field intensity is taking into account the excitation conditions determined by both the angle of incidence and the incident photon energy. By means of a nanolayered specimen consisting of light elements and transition metals the XSW based GIXRF quantification procedure is demonstrated and compared to other approaches.