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  • 51.
    Arwin, Hans
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Mendoza-Galván, A.
    Cinvestav, Querétaro, Mexico.
    Järrendahl, Kenneth
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Dmitriev, A.
    Chalmers University of Technology, Department of Applied Physics.
    Pakizeh, T.
    Chalmers University of Technology, Department of Applied Physics.
    Käll, M.
    Chalmers University of Technology, Department of Applied Physics.
    Artificial Magnetism in Gold-Silica-Gold Metamaterials - an ellipsometric Study2009Conference paper (Other academic)
  • 52.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Piacham, Theeraphon
    Pure and applied biochemistry Lunds universitet.
    Josell, Åsa
    Pure and applied biochemsitry Lunds universitet.
    Prachayasittikul, Virapong
    Department of Clinical Microbiology Mahidol University, Bangkok.
    Ye, Lei
    Pure and applied biochemistry Lunds universitet.
    Molecularly imprinted polymer thin films on quartz crystal microbalance using a surface bound photo-radical initiator2005In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 536, p. 191-196Article in journal (Refereed)
  • 53.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Poksinski, Michal
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Protein-Surface Interactions Studied with Internal Reflection Ellipsometry2004In: AVS 51st International Symposium Exhibition,2004, Anaheim: Anaheim Convention Center , 2004, p. 1010-Conference paper (Refereed)
  • 54.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Poksinski, Michal
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Total Internal Reflection Ellipsometry: a tool for analysis of ultrathin films on metal surfaces2006In: 4th Workshop Ellipsometry,2006, 2006Conference paper (Other academic)
  • 55.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Poksinski, Michal
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Total Internal Reflection Ellipsometry: monitoring of proteins on thin metal films2006In: Proteins on surfaces / [ed] Arwin H, Poksinski M, Johansen K., Berlin, Heidelberg: Springer Verlag , 2006, p. 105-118Chapter in book (Other academic)
    Abstract [en]

    A measurement technique based on ellipsometry performed under conditions of total internal reflection is presented here. This technique is called total internal reflection ellipsometry (TIRE). When extended with the surface plasmon resonance effect, TIRE becomes a powerful tool for monitoring protein adsorption on thin metal films. A brief description of TIRE is presented here together with some examples of measurement system setups. Two examples of applications are included, followed by a short presentation of possible future applications of TIRE.

  • 56.
    Arwin, Hans
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Poksinski, Michal
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Johansen, Knut
    Scientific Engineering QED, Linköping, Sweden.
    Enhancement in ellipsometric thin film sensitivity near surface plasmon resonance conditions2008In: Physica Status Solidi (a) applications and materials science, ISSN 1862-6300, E-ISSN 1862-6319, Vol. 205, no 4, p. 817-820Article in journal (Refereed)
    Abstract [en]

    Ellipsometry used in internal reflection mode exhibits enhanced thin film sensitivity if operated close to surface plasmon resonance conditions. Compared to conventional ellipsometry, the changes in the ellipsometric parameter Δ are several orders of magnitude larger. Here, the origin of this large sensitivity is discussed by analysing thin film approximations of the complex reflectance ratio. It is found that the thickness sensitivity in Δ is proportional to the inverse of the difference between the intrinsic and the radiation-induced damping of the surface plasmons.

  • 57.
    Arwin, Hans
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Poksinski, Michal
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Johansen, Knut
    Scientific Engineering QED, Linköping, Sweden.
    Total internal reflection ellipsometry: principles and applications2004In: Applied Optics, ISSN 0003-6935, E-ISSN 1539-4522, Vol. 43, no 15, p. 3028-3036Article in journal (Refereed)
    Abstract [en]

    A concept for a measurement technique based on ellipsometry in conditions of total internal reflection is presented. When combined with surface plasmon resonance (SPR) effects, this technique becomes powerful for monitoring and analyzing adsorption and desorption on thin semitransparent metal films as well as for analyzing the semitransparent films themselves. We call this technique total internal reflection ellipsometry (TIRE). The theory of ellipsometry under total internal reflection combined with SPR is discussed for some simple cases. For more advanced cases and to prove the concept, simulations are performed with the Fresnel formalism. The use of TIRE is exemplified by applications in protein adsorption, corrosion monitoring, and adsorption from opaque liquids on metal surfaces. Simulations and experiments show greatly enhanced thin-film sensitivity compared with ordinary ellipsometry.

  • 58.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Sarkar, Sabyasachi
    IFM .
    Woollam, J.
    Investigation of the use of IR ellipsometry for the detection of biological molecules2006In: American Vacuum Society 53 Int Symposium,2006, 2006Conference paper (Other academic)
  • 59.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Tazawa, M
    Kakiuchida, H
    Xu, G
    Jin, P
    Optical constants of vacuum evaporated SiO film and an application2005In: MRS-ICAM2005,2005, 2005Conference paper (Other academic)
  • 60.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Thompson, D.W.
    Woollam, J.A.
    Infrared Ellipsometry Studies on Protein Layers: Model Dielectric Functions and Temperature Effects2006In: 4th Workshop Ellipsometry,2006, 2006Conference paper (Other academic)
  • 61.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Thompson, D.W.
    Woollam, J.A.
    Temperature Stability of Protein Monolayers Studied by Ellipsometry in the Infrared, Visible and Ultraviolet Spectral Regions2006In: American Vacuum Society 53 Int Symposium,2006, 2006Conference paper (Other academic)
  • 62.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Wang, Guoliang
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Jansson, Roger
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Gas sensing based on ellipsometric measurement on porous silicon2003In: Physica status solidi. A, Applied research, ISSN 0031-8965, E-ISSN 1521-396X, Vol. 197, no 2, p. 518-522Conference paper (Other academic)
    Abstract [en]

    Ellipsometry has sufficient sensitivity for sensor applications and is here used as an optical readout method in a gas sensing system. Porous silicon is used as sensing layers in which vapors of solvents can adsorb and condensate due to capillary effects. A miniaturized multi-beam ellipsometer system is proposed and the concept is demonstrated by measurements on alcohol vapors. Optimization of the sensor system is discussed and improvement of sensitivity and alteration of selectivity by metal deposition in porous silicon layers are presented.

  • 63.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Wiklund, Henrik
    IFM .
    Järrendahl, Kenneth
    TFK .
    Calculation of optical properties of complex surface structures using FEM2006In: Optikdagen 2006,2006, 2006Conference paper (Other academic)
  • 64.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Wiklund, Henrik
    IFM .
    Järrendahl, Kenneth
    TFK .
    Calculation of optical properties of complex surface structures using FEM2006In: European Optical Society Annual Meeting,2006, 2006Conference paper (Other academic)
  • 65.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Woollam, John A.
    Department of electrical engineering University of Nebraska.
    Thompson, Dan W.
    Department of electrical engineering University of Nebraska.
    Model dielectric functions for adsorbed protein layers2005In: American Vacumm Society 52 Int Symposium and Exhibition,2005, 2005Conference paper (Other academic)
  • 66.
    Arwin, Hans
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Wronkowska, A A
    Firszt, F
    Wronkowski, A
    Wakula, M
    Strzalkowski, K
    Paszkowicz, W
    Characterisation of Cd1-x-yZnxBeySe crystals by spectroscopic ellipsometry and luminescence2006In: Physica Status Solidi. C, Current topics in solid state physics, ISSN 1610-1634, E-ISSN 1610-1642, p. 1193-1196Article in journal (Refereed)
  • 67.
    Ashkenov, N.
    et al.
    Universität Leipzig, Fak. F. Phys. and Geowissenschaften, Inst. F. Experimentelle Physik II, Linnéstrasse 5, 04103 Leipzig, Germany.
    Mbenkum, B.N.
    Universität Leipzig, Fak. F. Phys. and Geowissenschaften, Inst. F. Experimentelle Physik II, Linnéstrasse 5, 04103 Leipzig, Germany.
    Bundesmann, C.
    Universität Leipzig, Fak. F. Phys. and Geowissenschaften, Inst. F. Experimentelle Physik II, Linnéstrasse 5, 04103 Leipzig, Germany.
    Riede, V.
    Universität Leipzig, Fak. F. Phys. and Geowissenschaften, Inst. F. Experimentelle Physik II, Linnéstrasse 5, 04103 Leipzig, Germany.
    Lorenz, M.
    Universität Leipzig, Fak. F. Phys. and Geowissenschaften, Inst. F. Experimentelle Physik II, Linnéstrasse 5, 04103 Leipzig, Germany.
    Spemann, D.
    Universität Leipzig, Fak. F. Phys. and Geowissenschaften, Inst. F. Experimentelle Physik II, Linnéstrasse 5, 04103 Leipzig, Germany.
    Kaidashev, E.M.
    Universität Leipzig, Fak. F. Phys. and Geowissenschaften, Inst. F. Experimentelle Physik II, Linnéstrasse 5, 04103 Leipzig, Germany, Rostov State University, Mech./Appl. Math. Research Institute, 200/1 Stachky Avenue, Rostov-on-Don 344090, Russian Federation.
    Kasic, A.
    Universität Leipzig, Fak. F. Phys. and Geowissenschaften, Inst. F. Experimentelle Physik II, Linnéstrasse 5, 04103 Leipzig, Germany.
    Schubert, M.
    Universität Leipzig, Fak. F. Phys. and Geowissenschaften, Inst. F. Experimentelle Physik II, Linnéstrasse 5, 04103 Leipzig, Germany.
    Grundmann, M.
    Universität Leipzig, Fak. F. Phys. and Geowissenschaften, Inst. F. Experimentelle Physik II, Linnéstrasse 5, 04103 Leipzig, Germany.
    Wagner, G.
    Inst. F. Nichtklassische Chem. e.V., Universität Leipzig, Permoserstraße 15, 04318 Leipzig, Germany.
    Neumann, H.
    Inst. F. O. e.V., Permoserstrasse 15, 04303 Leipzig, Germany.
    Darakchieva, Vanya
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Materials Science .
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Monemar, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Materials Science .
    Infrared dielectric functions and phonon modes of high-quality ZnO films2003In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 93, no 1, p. 126-133Article in journal (Refereed)
    Abstract [en]

    A study was performed on the phonon modes and infrared dielectric functions of high-quality ZnO thin films. The pulsed laser deposition technique was used to deposit the ZnO films on c-plane sapphire substrates and were investigated by high-resolution transmission electron microscopy, high-resolution x-ray diffraction and Rutherford backscattering experiments. The accurate long-wavelength dielectric constant limits of the films were also obtained and were compared with near-band-gap index-of-refraction data upon the Lyddane-Sachs-Teller relation for both film and bulk samples. It was found that the phonon modes of the film were highly consistent with those of the bulk sample.

  • 68.
    Bakker, Jimmy
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Filippini, Daniel
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Biosensor for home use: using the computer as ellipsometer2006Other (Other (popular science, discussion, etc.))
    Abstract [en]

    Konferensbidrag (muntligt-1:a pris) vid "EUROPT(R)ODE VIII, Tübingen, Germany, 2-5 april

  • 69.
    Bakker, Jimmy
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Filippini, Daniel
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Fluorescence based sensing in a CSPT setup2005In: Medicinteknikdagarna,2005, 2005Conference paper (Other academic)
  • 70. Order onlineBuy this publication >>
    Bakker, Jimmy W. P.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics. Linköping University, The Institute of Technology.
    New methodology for optical sensing and analysis2004Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis describes the research I have done, and partly will do, during my time as a PhD student in the laboratory of Applied Optics at Linköping University. Due to circumstances beyond the scope of this book, this incorporates three quite different projects. The first two, involving gas sensing and measuring on paper with ellipsometry, have been discontinued, whereas the third one, measuring fluorescence with a computer screen and web camera, is in full progress and will be until I complete my studies.

    Thus the purpose of this work also has several aspects. Partly, it describes performed research and its results, as well as theoretical background. On the other hand, it provides practical and theoretical background necessary for future work. While the three projects are truly quite different, each of them has certain things in common with each of the other. This is certainly also true for the necessary theory. Two of them involve spectroscopic ellipsometry, for example, while another pair needs knowledge of color theory, etc. This makes it impossible to separate the projects, despite of their differences. Hopefully, these links between the different projects, connecting the different chapters, will make this work whole and consistent in its own way.

    List of papers
    1. Improvement of porous silicon based gas sensors by polymer modification
    Open this publication in new window or tab >>Improvement of porous silicon based gas sensors by polymer modification
    2003 (English)In: Physica Status Solidi (A), ISSN 0031-8965, Vol. 197, no 2, p. 378-381Article in journal (Refereed) Published
    Abstract [en]

    Gas sensing was performed using spectroscopic ellipsometry and porous silicon films. Modification of the porous layer by polymer deposition showed an increase in sensitivity to organic solvent vapor of up to 135%. The increase in sensitivity is strongly dependent on polymer concentration. At high concentrations, too much polymer is deposited, presumably blocking the pores, causing a decrease in sensitivity. At sufficiently low concentrations, the polymer causes a strong increase in sensitivity. This is assumed to be caused by the polymer being deposited inside the pores, where its interaction with the vapor influences the sensitivity. At very low concentration, the sensitivity approaches values obtained without polymer modification. The sensitivity increase is different for different vapors, pointing to possible selectivity enhancement.

    Keywords
    07.07.Df, 61.43.Gt, 78.67.Bf, 82.35.Gh
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13772 (URN)10.1002/pssa.200306529 (DOI)
    Available from: 2004-12-10 Created: 2004-12-10 Last updated: 2013-10-14
    2. Determination of refractive index of printed and unprinted paper using spectroscopic ellipsometry.
    Open this publication in new window or tab >>Determination of refractive index of printed and unprinted paper using spectroscopic ellipsometry.
    2004 (English)In: Thin Solid Films, ISSN 0040-6090, Vol. 455-456, p. 361-365Article in journal (Refereed) Published
    Abstract [en]

    An attempt is made to address the basic physical properties of printed and unprinted paper surfaces by using spectroscopic ellipsometry in the range 300–900 nm to determine the effective complex-valued refractive index N. Some simulations to address the effect of structural properties have also been done and a qualitative comparison with some other methods, in particular Brewster angle measurements, has been made. Unprinted paper and paper printed in different colors have been studied. The measured absorption properties matched the colors of the used inks well. The effects of roughness on the determined spectra of N are discussed. Simulations show that compared to other methods, like Brewster-angle reflectometry, spectroscopic ellipsometry provides a more accurate value of N, especially in wavelength regions were the color pigments show absorption.

    Keywords
    Spectroscopic ellipsometry; Paper surfaces; Optical properties; Gloss variation
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13773 (URN)10.1016/j.tsf.2004.01.024 (DOI)
    Available from: 2004-12-10 Created: 2004-12-10 Last updated: 2013-10-14
    3. Enhancing classification capabilities of computer screen photo-assisted fluorescence fingerprinting
    Open this publication in new window or tab >>Enhancing classification capabilities of computer screen photo-assisted fluorescence fingerprinting
    2005 (English)In: Sensors and Actuators B: Chemical, ISSN 0925-4005, Vol. 110, no 2, p. 190-194Article in journal (Refereed) Published
    Abstract [en]

    The separation of emission from transmitted light for the fingerprinting of fluorescent substances using a computer screen photo-assisted technique (CSPT) is demonstrated. CSPT is a technique for optical evaluation using a simple cell with just a standard computer set and a web camera as instrumentation. It has been demonstrated to be a versatile system for colorimetric and fluorescent fingerprinting. Here the omnidirectional property of fluorescent emission is utilized to separate it from the background, using a simple optical arrangement compatible with CSPT purposes. This enhances the classification capabilities and makes classification at sub-μM concentrations possible.

    Keywords
    Computer screen photo-assisted technique; Fluorescence; Spectral fingerprinting; Bioassays; Home tests
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13774 (URN)10.1016/j.snb.2005.01.046 (DOI)
    Available from: 2004-12-10 Created: 2004-12-10 Last updated: 2009-09-08
    Download full text (pdf)
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  • 71. Order onlineBuy this publication >>
    Bakker, Jimmy W. P.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics. Linköping University, The Institute of Technology.
    Optical Detection Using Computer Screen Photo-assisted Techniques and Ellipsometry2006Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Two main subjects, ellipsometry and computer screen photo-assisted techniques (CSPT), form the main line in this thesis. Ellipsometry is an optical technique based on the detection of polarization changes of light upon interaction with a sample. As most optical detection techniques it is non-intrusive and an additional advantage is its high surface sensitivity: thickness resolution in the order of pm can in principle be achieved. Therefore, ellipsometry is widely used as a technique for determination of optical constants and layer thickness for thin-layer structures. Lately ellipsometry has also been proposed for sensing applications, utilizing the detection of changes in the properties of thin layers. One application is described in this thesis concerning the detection of volatile organic solvents in gas phase using modified porous silicon layers, fabricated by electrochemical etching of silicon to create nm-sized pores. This greatly increases the surface area, promoting gas detection because the number of adsorption sites increases. Other applications of ellipsometry discussed in this thesis are based on combination with CSPT.

    CSPT is a way to exploit existing optical techniques for use in low-cost applications. In CSPT the computer screen itself is used as a (programmable) light source for optical measurements. For detection a web camera can be used and the whole measurement platform is formed by the computer. Since computers are available almost everywhere, this is a promising way to create optical measurement techniques for widespread use, for example in home-diagnostics. Since the only thing that needs to be added is a sample holder governing the physical or chemical process and directing the light, the cost can be kept very low. First, the use of CSPT for the measurement of fluorescence is described. Fluorescence is used in many detection applications, usually by chemically attaching a fluorescent marker molecule to a suitable species in the process and monitoring the fluorescent emission. The detection of fluorescence is shown to be possible using CSPT, first in a cuvette-based setup, then using a custom designed micro array. In the latter, polarizers were used for contrast enhancement, which in turn led to the implementation of an existing idea to test CSPT for ellipsometry measurements. In a first demonstration, involving thickness measurement of silicon dioxide on silicon, a thickness resolution in the order of nm was already achieved. After improvement of the system, gradients in protein layers could be detected, opening the door toward biosensor applications. Some further development will be needed to make the CSPT applications described here ready for the market, but the results so far are certainly promising.

    List of papers
    1. Improvement of porous silicon based gas sensors by polymer modification
    Open this publication in new window or tab >>Improvement of porous silicon based gas sensors by polymer modification
    2003 (English)In: Physica Status Solidi (A), ISSN 0031-8965, Vol. 197, no 2, p. 378-381Article in journal (Refereed) Published
    Abstract [en]

    Gas sensing was performed using spectroscopic ellipsometry and porous silicon films. Modification of the porous layer by polymer deposition showed an increase in sensitivity to organic solvent vapor of up to 135%. The increase in sensitivity is strongly dependent on polymer concentration. At high concentrations, too much polymer is deposited, presumably blocking the pores, causing a decrease in sensitivity. At sufficiently low concentrations, the polymer causes a strong increase in sensitivity. This is assumed to be caused by the polymer being deposited inside the pores, where its interaction with the vapor influences the sensitivity. At very low concentration, the sensitivity approaches values obtained without polymer modification. The sensitivity increase is different for different vapors, pointing to possible selectivity enhancement.

    Keywords
    07.07.Df, 61.43.Gt, 78.67.Bf, 82.35.Gh
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13772 (URN)10.1002/pssa.200306529 (DOI)
    Available from: 2004-12-10 Created: 2004-12-10 Last updated: 2013-10-14
    2. Enhancing classification capabilities of computer screen photo-assisted fluorescence fingerprinting
    Open this publication in new window or tab >>Enhancing classification capabilities of computer screen photo-assisted fluorescence fingerprinting
    2005 (English)In: Sensors and Actuators B: Chemical, ISSN 0925-4005, Vol. 110, no 2, p. 190-194Article in journal (Refereed) Published
    Abstract [en]

    The separation of emission from transmitted light for the fingerprinting of fluorescent substances using a computer screen photo-assisted technique (CSPT) is demonstrated. CSPT is a technique for optical evaluation using a simple cell with just a standard computer set and a web camera as instrumentation. It has been demonstrated to be a versatile system for colorimetric and fluorescent fingerprinting. Here the omnidirectional property of fluorescent emission is utilized to separate it from the background, using a simple optical arrangement compatible with CSPT purposes. This enhances the classification capabilities and makes classification at sub-μM concentrations possible.

    Keywords
    Computer screen photo-assisted technique; Fluorescence; Spectral fingerprinting; Bioassays; Home tests
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13774 (URN)10.1016/j.snb.2005.01.046 (DOI)
    Available from: 2004-12-10 Created: 2004-12-10 Last updated: 2009-09-08
    3. Two-dimensional micro array fluorescence fingerprinting with a computer screen photo-assisted technique
    Open this publication in new window or tab >>Two-dimensional micro array fluorescence fingerprinting with a computer screen photo-assisted technique
    2005 (English)In: Spectral Imaging: Instrumentation, Applications, and Analysis III, 2005, p. 9-15Conference paper, Published paper (Other academic)
    Abstract [en]

    Detection and classification of fluorescent dyes are demonstrated using a computer screen photo-assisted technique (CSPT). This technique has previously been demonstrated for analyzing fluorescence from 96 wells microtiterplates (200 µl per well) and from a single cuvette with some optics to enhance sensitivity. In this work a custom designed array of wells with a volume of approximately 1 mu;l is used. In order to measure such small volumes without saturating the detector, the transmitted light is masked by placing the sample between two crossed polarizers. This arrangement blocks nearly all the transmitted light, while the emitted light, which is nearly unpolarized, can still be detected. The lowest amount (concentration x volume) of analyte detectable in this setup is about 40 times smaller than in the previous setups.

    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-13835 (URN)10.1117/12.589586 (DOI)
    Available from: 2006-05-04 Created: 2006-05-04 Last updated: 2009-04-28
    4. Computer screen photo-assisted off-null ellipsometry
    Open this publication in new window or tab >>Computer screen photo-assisted off-null ellipsometry
    2006 (English)In: Applied Optics, ISSN 1559-128X, E-ISSN 2155-3165, Vol. 45, no 30, p. 7795-7799Article in journal (Refereed) Published
    Abstract [en]

    The ellipsometric measurement of thickness is demonstrated using a computer screen as a light source and a webcam as a detector, adding imaging off-null ellipsometry to the range of available computer screen photoassisted techniques. The results show good qualitative agreement with a simplified theoretical model and a thickness resolution in the nanometer range is achieved. The presented model can be used to optimize the setup for sensitivity. Since the computer screen serves as a homogeneous large area illumination source, which can be tuned to different intensities for different parts of the sample, a large sensitivity range can be obtained without sacrificing thickness resolution.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13836 (URN)10.1364/AO.45.007795 (DOI)
    Available from: 2006-05-04 Created: 2006-05-04 Last updated: 2017-12-13
    5. Non-labeled immunodetection with a computer screen photo-assisted technique
    Open this publication in new window or tab >>Non-labeled immunodetection with a computer screen photo-assisted technique
    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:liu:diva-13837 (URN)
    Available from: 2006-05-04 Created: 2006-05-04 Last updated: 2010-01-13
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    FULLTEXT01
  • 72.
    Bakker, Jimmy W. P.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Wang, Guoliang
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Järrendahl, K.
    Improvement of porous silicon based gas sensors by polymer modification2003In: Physica Status Solidi (A), ISSN 0031-8965, Vol. 197, no 2, p. 378-381Article in journal (Refereed)
    Abstract [en]

    Gas sensing was performed using spectroscopic ellipsometry and porous silicon films. Modification of the porous layer by polymer deposition showed an increase in sensitivity to organic solvent vapor of up to 135%. The increase in sensitivity is strongly dependent on polymer concentration. At high concentrations, too much polymer is deposited, presumably blocking the pores, causing a decrease in sensitivity. At sufficiently low concentrations, the polymer causes a strong increase in sensitivity. This is assumed to be caused by the polymer being deposited inside the pores, where its interaction with the vapor influences the sensitivity. At very low concentration, the sensitivity approaches values obtained without polymer modification. The sensitivity increase is different for different vapors, pointing to possible selectivity enhancement.

  • 73.
    Bakker, Jimmy. W. P.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Bryntse, G.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Determination of refractive index of printed and unprinted paper using spectroscopic ellipsometry.2004In: Thin Solid Films, ISSN 0040-6090, Vol. 455-456, p. 361-365Article in journal (Refereed)
    Abstract [en]

    An attempt is made to address the basic physical properties of printed and unprinted paper surfaces by using spectroscopic ellipsometry in the range 300–900 nm to determine the effective complex-valued refractive index N. Some simulations to address the effect of structural properties have also been done and a qualitative comparison with some other methods, in particular Brewster angle measurements, has been made. Unprinted paper and paper printed in different colors have been studied. The measured absorption properties matched the colors of the used inks well. The effects of roughness on the determined spectra of N are discussed. Simulations show that compared to other methods, like Brewster-angle reflectometry, spectroscopic ellipsometry provides a more accurate value of N, especially in wavelength regions were the color pigments show absorption.

  • 74.
    Bakker, Jimmy W. P.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Filippini, Daniel
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Enhancing classification capabilities of computer screen photo-assisted fluorescence fingerprinting2005In: Sensors and Actuators B: Chemical, ISSN 0925-4005, Vol. 110, no 2, p. 190-194Article in journal (Refereed)
    Abstract [en]

    The separation of emission from transmitted light for the fingerprinting of fluorescent substances using a computer screen photo-assisted technique (CSPT) is demonstrated. CSPT is a technique for optical evaluation using a simple cell with just a standard computer set and a web camera as instrumentation. It has been demonstrated to be a versatile system for colorimetric and fluorescent fingerprinting. Here the omnidirectional property of fluorescent emission is utilized to separate it from the background, using a simple optical arrangement compatible with CSPT purposes. This enhances the classification capabilities and makes classification at sub-μM concentrations possible.

  • 75.
    Bakker, Jimmy W.P.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Filippini, Daniel
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Computer screen photo-assisted off-null ellipsometry2006In: Applied Optics, ISSN 1559-128X, E-ISSN 2155-3165, Vol. 45, no 30, p. 7795-7799Article in journal (Refereed)
    Abstract [en]

    The ellipsometric measurement of thickness is demonstrated using a computer screen as a light source and a webcam as a detector, adding imaging off-null ellipsometry to the range of available computer screen photoassisted techniques. The results show good qualitative agreement with a simplified theoretical model and a thickness resolution in the nanometer range is achieved. The presented model can be used to optimize the setup for sensitivity. Since the computer screen serves as a homogeneous large area illumination source, which can be tuned to different intensities for different parts of the sample, a large sensitivity range can be obtained without sacrificing thickness resolution.

  • 76.
    Bakker, Jimmy W.P.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Filippini, Daniel
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Immunodetection using computer screen photo-assisted ellipsometry2008In: Physica Status Solidi. C: Current Topics in Solid State Physics, ISSN 1862-6351, Vol. 5, no 5, p. 1431-1433Article in journal (Refereed)
    Abstract [en]

    Detection of antibody-antigen reactions is demonstrated by measuring changes in reflectance of light polarized parallel to the plane of incidence, using a computer screen as light source and a web camera as detector, giving results similar to traditional off-null ellipsometry and in accordance with a simplified theoretical model.

  • 77.
    Bakker, Jimmy W.P.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Filippini, Daniel
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Two-dimensional micro array fluorescence fingerprinting with a computer screen photo-assisted technique2005In: Spectral Imaging: Instrumentation, Applications, and Analysis III, 2005, p. 9-15Conference paper (Other academic)
    Abstract [en]

    Detection and classification of fluorescent dyes are demonstrated using a computer screen photo-assisted technique (CSPT). This technique has previously been demonstrated for analyzing fluorescence from 96 wells microtiterplates (200 µl per well) and from a single cuvette with some optics to enhance sensitivity. In this work a custom designed array of wells with a volume of approximately 1 mu;l is used. In order to measure such small volumes without saturating the detector, the transmitted light is masked by placing the sample between two crossed polarizers. This arrangement blocks nearly all the transmitted light, while the emitted light, which is nearly unpolarized, can still be detected. The lowest amount (concentration x volume) of analyte detectable in this setup is about 40 times smaller than in the previous setups.

  • 78.
    Bergqvist, Jonas
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Determination of optical constants and phase transition temperatures in polymer fullerene thin films for polymer solar cells2012Conference paper (Other academic)
    Abstract [en]

    Plastic photovoltaics combining semiconducting polymers with fullerene derivatives have the potentialto become the first cost efficient solar cells able to compete with fossil fuels. The maximum powerconversion efficiency is already 8.3%[1] , and new polymers arrive frequently in the search for efficienciesof 10%. As a first step in the screening of candidate materials, the optical constants of the purepolymer as well as the polymer blend with fullerenes are determined from Variable Angle SpectroscopicEllipsometry (VASE), using Tauc-Lorentz oscillator models, throughout the solar spectrum. Thesemodels are then used to predict the upper limits to photocurrent generation in devices, in transfermatrix simulations of the multilayer thin film photovoltaic devices. This forms an essential step in thechoice of materials for optimization in devices.Materials optics measurements are also used to deduce the phase diagram of polymer and polymerblend films. The glass transition temperature is very important for plastic solar cells and mustbe higher than the 80C a device can reach to avoid degradation during operation. Temperaturedependent ellipsometric measurements has proven to be a feasible way to determine phase transitionsin polymer thin films[2] . These transitions are displayed as a sudden change of the volumetricexpansion coefficient, and are manifested by an abrupt increase of thickness at the phase transitiontemperature. For thickness determination a Cauchy model is applied to the transparent infrared partof the spectra.References1. Z. He, C. Zhong, X. Huang, W-Y. Wong, H. Wu, L. Chen, S. Su, Y Cao, Advanced Materials 23, 4636(2011)2. M. Campoy-Quiles, P.G. Etchegoin, D.D.C. Bradley, Synthetic Metals 155, 279(2005)

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    WSE12
  • 79.
    Bergqvist, Jonas
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    In situ reflectance imaging of organic thin film formation from solution2012Conference paper (Other academic)
  • 80.
    Bergqvist, Jonas
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, Faculty of Science & Engineering.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Uniaxial anisotropy in PEDOT:PSS electrodes enhances the photo current at oblique incidence in organic solar cells2015Manuscript (preprint) (Other academic)
    Abstract [en]

    In this work an uniaxial anisotropic treatment of the transparent conductor PEDOT:PSS is included in the transfer matrix method (TMM), used to calculate the optical power dissipation in organic solar cells. PEDOT:PSS is known to be anisotropic and exhibit a weaker absorption and lower refractive index in the out of plane direction. For p-polarized light at large oblique incidence the inclusion of anisotropy show a gain of over 10% for the maximum photocurrent as compared to an isotropic treatment. Due to the interference in devices with reflecting bottom electrodes, the active layer absorption gain is not always occurring for the wavelengths with highest dichroism. This work show that using PEDOT:PSS as top electrode further strengthens the argument that thin film solar cells perform better than their silicon counterparts under oblique incidence. We also confirm previous studies showing that the optical interference maxima is shifted to slightly thicker films for oblique incidence for solar cells with reflective bottom electrodes.

  • 81.
    Bergqvist, Jonas
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Mauger, Scott
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Tvingstedt, Kristofer
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    In situ reflectance imaging of organic thin film formation from solution deposition2013In: Solar Energy Materials and Solar Cells, ISSN 0927-0248, E-ISSN 1879-3398, Vol. 114, p. 89-98Article in journal (Refereed)
    Abstract [en]

    In this work we present reflectance imaging as a suitable method for in situ monitoring of the drying process of film formation for organic photovoltaics (OPV) over large areas, as well as for lab-scale spin-coating. The drying wet film is illuminated with a narrow bandwidth LED with the specularly reflected light recorded by a video camera as the film dries and forms the active layer of the OPV cell. The interference fringes generated by the thinning wet film can be used to measure the rate of solvent evaporation and the drying time. Subsequent mapping elucidates variations in drying conditions over the substrate, which lead to variations in morphology formation. The technique is suitable for tracking thickness variations of the dry film, with a sensitivity of 10 nm, by comparing the intensity of the reflected light from the dry film to simulated interference conditions calculated for each thickness. The drying process is furthermore accurately simulated by an optical model considering the changes in refractive index as the amount of solvent decreases with respect to the solid content. This non-invasive in situ method represents an important monitoring tool for future large scale OPV manufacturing where high performing morphologies with uniform thickness have to be formed over very large areas.

  • 82.
    Bergqvist, Jonas
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Tvingstedt, Kristofer
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    In situ reflectance imaging of organic thin film formation from solution2012Conference paper (Other academic)
    Abstract [en]

    The rapid progress of organic photovoltaic devices during the last decade, with power conversion efficiencies now exceeding 8%, has brought the technology close to an industrial breakthrough. For polymer solar cells, roll to roll printing is desired to gain the production advantage. The formation of the photoactive material from solutions needs to be controlled and optimized. Therefore a suitable method to monitor the deposition process is needed as deviations of drying times1 and drying rates2 during the coating process have proven to generate morphology variations causing variations in photocurrent generation.

    Here we demonstrate how reflectance imaging can be used to monitor the drying process, both for spin coating and blade coating deposition. A blue LED is used as light source to generate specular reflections imaged by a CMOS camera. The thinning of the wet film can then be observed by thin film interference, and can be recorded for each pixel. This enables an estimation of the evaporation rate for each pixel mapped over the substrate. For spin coating the evaporation rate is shown to increase with the distance from the rotation center, whereas the air flow is the determining parameter during blade coating. By mapping the times when interference ceases, lateral variations in drying time are visualized. Furthermore the quenching of polymer photoluminescence during the drying process can be visualized, thus creating a possibility to estimate morphological variations. Moreover lateral thickness variations of the dry film can be visualized by scanning ellipsometry. After depositing a top electrode photocurrent images can be generated by a laser scanning method. This allows for a direct comparison of drying conditions and photocurrent generation.  The possibility to monitor the thin film formation as well as lateral variations in thickness in-situ by a non-invasive method, is an important step for future large scale applications where stable high performing generating morphologies have to be formed over large areas.

    1Schmidt-Hansberg, B.; Sanyal, M.; Klein, M.F.G.; Pfaff, M.; Schnabel, N.; Jaiser, S.; Vorobiev, A.; Müller, E.; Colsmann, A.; Scharfer, P.; Gerthsen, D.; Lemmer, U.; Barrena, E.; and Schabel, W., ACS Nano 5 , 2011, 8579-8590

    2 Hou, L.; Wang, E.; Bergqvist, J.; Andersson, V.B.; Wang, Z.; Müller, C.; Campoy-Quiles, M.; Andersson, M.R.; Zhang, F.; Inganäs, O.,Adv. Func. Mat. 21 , 2011, 3169–3175

  • 83. Order onlineBuy this publication >>
    Berlind, Torun
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics. Linköping University, The Institute of Technology.
    Carbon Nitride: Characterization and Protein Interactions2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis concerns synthesis and characterization of carbon-based materials and theinvestigation of the possible use, of a selection of these materials, in biomedicalapplications. Protein adsorption and blood plasma tests were used for this purposeutilizing a surface sensitive technique called spectroscopic ellipsometry.

    The materials were synthesized by physical vapor deposition and characterizedregarding microstructure, mechanical properties and optical properties. The ternaries BC-N and Si-C-N as well as carbon and carbon nitrides (CNx) of different microstructureshave been examined. In the B-C-N work, the intention was to investigate the possibilityto combine the two materials CNx and BN, interesting on their own regarding highhardness and extreme elasticity, to produce a material with even better properties.Theoretical calculations were performed to elucidate the different element substitutionsand defect arrangements in the basal planes promoting curvature in the fullerene-likemicrostructure. The Si-C-N ternary was investigated with the consideration of finding away to control the surface energy for certain applications. Amorphous carbon and threemicrostructures of CNx were analyzed by spectroscopic ellipsometry in the UV-VIS-NIRand IR spectral ranges in order to get further insight into the bonding structure of thematerial.

    In the second part of this work focus was held on studies of macromolecularinteractions on silicon, carbon and CNx film surfaces using ellipsometry. One purposewas to find relevance (or not) for these materials in biological environments. Materials for bone replacement used today, e.g. stainless steel, cobalt-chromium alloys andtitanium alloys suffer from corrosion in body fluids, generation of wear particles inarticulating systems, infections and blood coagulation and cellular damage leading toimpaired functionality and ultimately to implant failure. Artificial heart valves made ofpyrolytic carbon are used today, with friction and wear problems. Thus, there is still aneed to improve biomaterials. The aim of the fourth paper was to investigate theinteraction between carbon-based materials and proteins. Therefore, amorphous carbon(a-C), amorphous (a), graphitic (g) and fullerene-like (FL) CNx thin films were exposedto human serum albumin and blood plasma and the amount of protein was measured insitu using spectroscopic ellipsometry. Surface located and accessible proteins after blood plasma incubations were eventually identified through incubations in antibody solutions.

    Antibody exposures gave indications of surface response to blood coagulation,complement activation and clotting. The a-C and FL-CNx films might according to theresults have a future in soft tissue applications due to the low immuno-activity, whereasthe g-CNx film possibly might be a candidate for bone replacement applications.

    "Layered" structures of fibrinogen, a fibrous but soft protein involved in manyprocesses in our body, were grown in situ and dynamically monitored by ellipsometry inorder to understand the adsorption process and molecule arrangement onto a siliconsurface.

    In the last paper of this thesis, the effects of ion concentration and proteinconcentration on the refractive index of water-based solutions used in in situ ellipsometrymeasurements were demonstrated and spectral refractive index data for water solutionswith different ionic strengths and protein concentrations have been provided.

    List of papers
    1. Microstructure, mechanical properties, and wetting behaviorof Si-C-N thin films grown by reactive magnetron sputtering
    Open this publication in new window or tab >>Microstructure, mechanical properties, and wetting behaviorof Si-C-N thin films grown by reactive magnetron sputtering
    2001 (English)In: Surface and Coatings Technology, ISSN 0257-8972, Vol. 141, no 2-3, p. 145-155Article in journal (Refereed) Published
    Abstract [en]

    Silicon–carbon–nitride (Si–C–N) thin films were deposited by reactive magnetron co-sputtering of C and Si targets in a mixed Ar/N2 discharge. Films were grown to a thickness of more than 0.5 μm on graphite and Si(001) substrates held at a negative floating potential of −35 V, and substrate temperature between 100 and 700°C. The total pressure was constant at 0.4 Pa (3 mtorr), and the nitrogen fraction in the gas mixture was varied between 0 and 100%. As-deposited films were analyzed with respect to composition, state of chemical bonding, microstructure, mechanical properties, and wetting behavior by Rutherford backscattering spectroscopy (RBS), energy dispersive spectroscopy (EDS), X-ray photoelectron spectrometry (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), nanoindentation and contact angle measurements, respectively. Depending on the deposition condition, ternary SixCyNz films within the composition range 1≤x≤34 at.%, 34≤y≤81 at.%, and 16.5≤z≤42 at.% were prepared with a textured, amorphous-to-graphite-like microstructure. For Si–C–N films with low Si content, C---C, C---N and Si---C bonds were present. At higher Si content, N preferentially bonds to Si, while less C---N bonds were observed. Films containing more than 12 at.% of Si contained widely dispersed crystallites, 2–20 nm in diameter. Incorporation of a few at.% Si resulted in a dramatic reduction of the film surface energy compared to pure CN films. The measured contact angles using distilled water and glycerol liquids were for some films comparable with those on a polytetrafluoroethylene (PTFE), Teflon® surface. The hardness of Si–C–N films could be varied over the range 9–28 GPa.

    Place, publisher, year, edition, pages
    Elsevier, 2001
    Keywords
    Silicon-carbon-nitride thin films; Magnetron sputtering; Properties
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-19703 (URN)10.1016/S0257-8972(01)01236-1 (DOI)
    Available from: 2009-07-16 Created: 2009-07-16 Last updated: 2016-08-31Bibliographically approved
    2. Fullerene-like B C N thin films a computational andexperimental study
    Open this publication in new window or tab >>Fullerene-like B C N thin films a computational andexperimental study
    Show others...
    2004 (English)In: Materials Science and Engineering B, Vol. 113, no 3, p. 242-247Article in journal (Refereed) Published
    Abstract [en]

    Ab initio calculations show that the energy cost for incorporating lattice defects such as pentagons and heptagons is significantly reduced for BCN compared to BN, thus promoting bending of basal planes in these compounds. Boron–carbon–nitride (Bsingle bondCsingle bondN) thin films with a fullerene-like (FL) microstructure were then deposited by dual cathode magnetron sputtering from C and B4C targets. Up to 1 μm thick films were grown at a total gas pressure of 3 mTorr (0.4 Pa) in varying Ar/N2 ratios, and substrate temperatures between 225 and 350 °C. Compositional and microstructural studies were performed using RBS, SEM and HREM, respectively. Depending on the deposition condition, ternary BxCyNz films with fullerene-like microstructure could be prepared in agreement with the calculations within the composition range 0 ≤ x ≤ 53, 15 ≤ y ≤ 62, and 24 ≤ z ≤ 50 at.%. Fullerene-like structures also tend to form at lower temperatures in the case of BCN compared to CN. Nanoindentation measurements show that all BxCyNz films exhibited a highly elastic response independent of elemental composition. In addition, the calculations suggest a driving force for C and BN phase separation.

    Place, publisher, year, edition, pages
    Elsevier, 2004
    Keywords
    Ab initio calculations; Fullerene-like materials; BCN compounds; Thin films Reactive magnetron sputtering
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-19704 (URN)10.1016/j.mseb.2004.08.013 (DOI)
    Available from: 2009-07-16 Created: 2009-07-16 Last updated: 2018-05-28Bibliographically approved
    3. Spectroscopic ellipsometry characterization of amorphous carbon and amorphous,graphitic and fullerene-like carbon nitride thin films
    Open this publication in new window or tab >>Spectroscopic ellipsometry characterization of amorphous carbon and amorphous,graphitic and fullerene-like carbon nitride thin films
    Show others...
    2009 (English)In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 517, no 24, p. 6652-6658Article in journal (Refereed) Published
    Abstract [en]

    Carbon nitride (CNx) and amorphous carbon (a-C) thin films are deposited by reactive magnetron sputtering onto silicon (001) wafers under controlled conditions to achieve amorphous, graphitic and fullerene-like microstructures. As-deposited films are analyzed by Spectroscopic Ellipsometry in the UV–VIS–NIR and IR spectral ranges in order to get further insight into the bonding structure of the material. Additional characterization is performed by High Resolution Transmission Electron Microscopy, X-ray Photoelectron Spectroscopy, and Atomic Force Microscopy. Between eight and eleven resonances are observed and modeled in the ellipsometrically determined optical spectra of the films. The largest or the second largest resonance for all films is a feature associated with C–N or C–C modes. This feature is generally associated with sp3 C–N or sp3 C–C bonds, which for the nitrogen-containing films instead should be identified as a three-fold or two-fold sp2 hybridization of N, either substituted in a graphite site or in a pyridine-like configuration, respectively. The π→πlow asterisk electronic transition associated with sp2 C bonds in carbon films and with sp2 N bonds (as N bonded in pyridine-like manner) in CNx films is also present, but not as strong. Another feature present in all CNx films is a resonance associated with nitrile often observed in carbon nitrides. Additional resonances are identified and discussed and moreover, several new, unidentified resonances are observed in the ellipsometric spectra.

    Place, publisher, year, edition, pages
    Elsevier, 2009
    Keywords
    Carbon nitride; Amorphous carbon; Spectroscopic ellipsometry; Spectral decomposition; Fullerene-like; Structural properties; X-ray photoelectron spectroscopy; Transmission electron microscopy
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-19705 (URN)10.1016/j.tsf.2009.04.065 (DOI)
    Note
    Original Publication: Torun Berlind, Andrej Furland, Zs. Czigany, Jörg Neidhardt, Lars Hultman and Hans Arwin, Spectroscopic ellipsometry characterization of amorphous carbon and amorphous,graphitic and fullerene-like carbon nitride thin films, 2009, Thin Solid Films, (517), 24, 6652-6658. http://dx.doi.org/10.1016/j.tsf.2009.04.065 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/ Available from: 2009-07-16 Created: 2009-07-16 Last updated: 2017-12-13Bibliographically approved
    4. Protein adsorption on thin films of carbon and carbon nitride monitored with in situ ellipsometry
    Open this publication in new window or tab >>Protein adsorption on thin films of carbon and carbon nitride monitored with in situ ellipsometry
    2011 (English)In: ACTA BIOMATERIALIA, ISSN 1742-7061, Vol. 7, no 3, p. 1369-1378Article in journal (Refereed) Published
    Abstract [en]

    Amorphous carbon and amorphous, graphitic and fullerene-like carbon nitride thin filmswere deposited by reactive magnetron sputtering and optically characterized withspectroscopic ellipsometry. The films were exposed to human serum albumin and theadsorption was monitored in situ using dynamic ellipsometry. From the ellipsometric data theadsorbed amount of proteins was quantified in terms of surface mass density using de Feijter'smodel. The results indicated larger adsorption of proteins onto the amorphous films comparedto the films with a more ordered microstructure. Complementary studies with labeled HSAusing radioimmunoassay showed up to 6 times higher protein adsorption compared to theellipsometry measurement which partly might be explained by differences in surfaceroughness (from 0.3 to 13 nm) among the films. The elutability of adsorbed labeled HSAusing unlabeled HSA and sodium dodecyl sulphate was low compared to a silicon reference.In addition, the four types of films were incubated in blood plasma followed by antifibrinogen,anti-HMWK or anti-C3c revealing the materials response to complement andcontact activation. Three of the films indicated immunoactivity, whereas the amorphouscarbon showed less immunoactivity compared to a titanium reference. All films showedindications of a stronger ability to initiate the intrinsic pathway of coagulation, compared tothe reference. Finally, the surfaces bone bonding ability was investigated by examination oftheir ability to form calcium phosphate (CaP) crystals in a simulated body fluid, with a-CNxdepositing most CaP after 21 days of incubation.

    Place, publisher, year, edition, pages
    Elsevier Science B.V. Amsterdam, 2011
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-19706 (URN)10.1016/j.actbio.2010.10.024 (DOI)000287643900049 ()
    Note
    Original Publication: Torun Berlind, Pentti Tengvall, Lars Hultman and Hans Arwin, Protein adsorption on thin films of carbon and carbon nitride monitored with in situ ellipsometry, 2011, ACTA BIOMATERIALIA, (7), 3, 1369-1378. http://dx.doi.org/10.1016/j.actbio.2010.10.024 Copyright: Elsevier Science B.V. Amsterdam http://www.elsevier.com/ Available from: 2009-07-16 Created: 2009-07-16 Last updated: 2016-08-31Bibliographically approved
    5. Formation and cross-linking of fibrinogen layers monitored with in situ spectroscopic ellipsometry
    Open this publication in new window or tab >>Formation and cross-linking of fibrinogen layers monitored with in situ spectroscopic ellipsometry
    2010 (English)In: Colloids and Surfaces B: Biointerfaces, ISSN 0927-7765, E-ISSN 1873-4367, Vol. 75, no 2, p. 410-417Article in journal (Other academic) Published
    Abstract [en]

    Thick matrices of fibrinogen with incorporation of a matrix metalloproteinaseinhibitor were covalently bonded on functionalized silicon surfaces using an ethyl-3-dimethyl-aminopropyl-carbodiimide and N-hydroxy-succinimide affinity ligand couplingchemistry. The growth of the structure was followed in situ using dynamic ellipsometryand characterized at steady-state with spectroscopic ellipsometry. The growth wascompared with earlier work on ex situ growth of fibrinogen layers studied by singlewavelength ellipsometry. It is found that in situ growth and ex situ growth yield differentstructural properties of the formed protein matrix. Fibrinogen matrices with thicknessesup to 58 nm and surface mass densities of 1.6 μg/cm2 have been produced.

    Keywords
    Fibrinogen, ellipsometry, coupling chemistry, protein adsorption
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-19707 (URN)10.1016/j.colsurfb.2009.09.013 (DOI)000276921900004 ()
    Note
    Original Publication: Torun Berlind, Michal Poksinski, Pentti Tengvall and Hans Arwin, Formation and cross-linking of fibrinogen layers monitored with in situ spectroscopic ellipsometry, Colloids and Surfaces B: Biointerfaces, 2010, (75), 2, 410-417. http://dx.doi.org/10.1016/j.colsurfb.2009.09.013 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/ Available from: 2009-07-16 Created: 2009-07-16 Last updated: 2017-12-13Bibliographically approved
    6. Effects of ion concentration on refractive indices offluids measured by the minimum deviation technique
    Open this publication in new window or tab >>Effects of ion concentration on refractive indices offluids measured by the minimum deviation technique
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    2008 (English)In: Physica Status Solidi. C, Current topics in solid state physics, ISSN 1610-1634, E-ISSN 1610-1642, Vol. 5, no 5, p. 1249-1252Article in journal (Refereed) Published
    Abstract [en]

    The prism minimum deviation technique has been used to measure the fluid dependence of refractive indices. Fluids with varying ion concentration (0 to 1.0 M) and varying protein concentration (0.01-10 mg/ml) have been examined and the measurements show that these parameters influence the refractive index values. Also it is shown by simulations that it is important to take the change of refractive index of the fluid into account when evaluating insitu protein adsorption measurements.

    Place, publisher, year, edition, pages
    Weinheim: WILEY-VCH Verlag GmbH & Co. KGaA, 2008
    Keywords
    07.60.Fs, 78.20.Ci, 87.14.E-
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-19708 (URN)10.1002/pssc.200777897 (DOI)
    Available from: 2009-07-16 Created: 2009-07-16 Last updated: 2017-12-13Bibliographically approved
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    Carbon Nitride: Characterization and Protein Interactions
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  • 84.
    Berlind, Torun
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Furland, Andrej
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Czigany, Zs.
    Research Institute for Technical Physics and Materials Science, Hungarian Academy of Sciences, H-1525 Budapest, Hungary.
    Neidhardt, Jörg
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Spectroscopic ellipsometry characterization of amorphous carbon and amorphous,graphitic and fullerene-like carbon nitride thin films2009In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 517, no 24, p. 6652-6658Article in journal (Refereed)
    Abstract [en]

    Carbon nitride (CNx) and amorphous carbon (a-C) thin films are deposited by reactive magnetron sputtering onto silicon (001) wafers under controlled conditions to achieve amorphous, graphitic and fullerene-like microstructures. As-deposited films are analyzed by Spectroscopic Ellipsometry in the UV–VIS–NIR and IR spectral ranges in order to get further insight into the bonding structure of the material. Additional characterization is performed by High Resolution Transmission Electron Microscopy, X-ray Photoelectron Spectroscopy, and Atomic Force Microscopy. Between eight and eleven resonances are observed and modeled in the ellipsometrically determined optical spectra of the films. The largest or the second largest resonance for all films is a feature associated with C–N or C–C modes. This feature is generally associated with sp3 C–N or sp3 C–C bonds, which for the nitrogen-containing films instead should be identified as a three-fold or two-fold sp2 hybridization of N, either substituted in a graphite site or in a pyridine-like configuration, respectively. The π→πlow asterisk electronic transition associated with sp2 C bonds in carbon films and with sp2 N bonds (as N bonded in pyridine-like manner) in CNx films is also present, but not as strong. Another feature present in all CNx films is a resonance associated with nitrile often observed in carbon nitrides. Additional resonances are identified and discussed and moreover, several new, unidentified resonances are observed in the ellipsometric spectra.

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    FULLTEXT01
  • 85.
    Berlind, Torun
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Hellgren, Niklas
    Frederick Seitz Materials Research Laboratory, University of Illinois, 104 South Goodwin Avenue, Urbana, IL 61801, USA.
    Johansson, Mats P.
    Thin Film Electronics AB, A°gatan 29, S-582 22 Link¨oping, Sweden.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Microstructure, mechanical properties, and wetting behaviorof Si-C-N thin films grown by reactive magnetron sputtering2001In: Surface and Coatings Technology, ISSN 0257-8972, Vol. 141, no 2-3, p. 145-155Article in journal (Refereed)
    Abstract [en]

    Silicon–carbon–nitride (Si–C–N) thin films were deposited by reactive magnetron co-sputtering of C and Si targets in a mixed Ar/N2 discharge. Films were grown to a thickness of more than 0.5 μm on graphite and Si(001) substrates held at a negative floating potential of −35 V, and substrate temperature between 100 and 700°C. The total pressure was constant at 0.4 Pa (3 mtorr), and the nitrogen fraction in the gas mixture was varied between 0 and 100%. As-deposited films were analyzed with respect to composition, state of chemical bonding, microstructure, mechanical properties, and wetting behavior by Rutherford backscattering spectroscopy (RBS), energy dispersive spectroscopy (EDS), X-ray photoelectron spectrometry (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), nanoindentation and contact angle measurements, respectively. Depending on the deposition condition, ternary SixCyNz films within the composition range 1≤x≤34 at.%, 34≤y≤81 at.%, and 16.5≤z≤42 at.% were prepared with a textured, amorphous-to-graphite-like microstructure. For Si–C–N films with low Si content, C---C, C---N and Si---C bonds were present. At higher Si content, N preferentially bonds to Si, while less C---N bonds were observed. Films containing more than 12 at.% of Si contained widely dispersed crystallites, 2–20 nm in diameter. Incorporation of a few at.% Si resulted in a dramatic reduction of the film surface energy compared to pure CN films. The measured contact angles using distilled water and glycerol liquids were for some films comparable with those on a polytetrafluoroethylene (PTFE), Teflon® surface. The hardness of Si–C–N films could be varied over the range 9–28 GPa.

  • 86.
    Berlind, Torun
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Poksinski, Michal
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Hultman, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics.
    Tengvall, Pentti
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Adsorption of human serum albumin on carbon nitride films studied with in-situ ellipsometry2005In: American Vacuum Society 52 Int Symposium and Exhibition,2005, 2005Conference paper (Other academic)
  • 87.
    Berlind, Torun
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Poksinski, Michal
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Hultman, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics.
    Tengvall, Pentti
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Bioadsorption studies on carbon nitride films using in-situ ellipsometry2005In: E-MRS spring meeting,2005, 2005Conference paper (Other academic)
  • 88.
    Berlind, Torun
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Poksinski, Michal
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Hultman, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics.
    Tengvall, Pentti
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Protein Adsorption on Carbon Nitride Films Studied with in situ Ellipsometry2007In: 4th International Conference on Spectroscopic Ellipsometry,2007, Linköping: Linköpings universitet , 2007, p. 246-Conference paper (Refereed)
  • 89.
    Berlind, Torun
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Poksinski, Michal
    Roxen IS AB, S-581 05 Linköping, Sweden.
    Tengvall, Pentti
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Formation and cross-linking of fibrinogen layers monitored with in situ spectroscopic ellipsometry2010In: Colloids and Surfaces B: Biointerfaces, ISSN 0927-7765, E-ISSN 1873-4367, Vol. 75, no 2, p. 410-417Article in journal (Other academic)
    Abstract [en]

    Thick matrices of fibrinogen with incorporation of a matrix metalloproteinaseinhibitor were covalently bonded on functionalized silicon surfaces using an ethyl-3-dimethyl-aminopropyl-carbodiimide and N-hydroxy-succinimide affinity ligand couplingchemistry. The growth of the structure was followed in situ using dynamic ellipsometryand characterized at steady-state with spectroscopic ellipsometry. The growth wascompared with earlier work on ex situ growth of fibrinogen layers studied by singlewavelength ellipsometry. It is found that in situ growth and ex situ growth yield differentstructural properties of the formed protein matrix. Fibrinogen matrices with thicknessesup to 58 nm and surface mass densities of 1.6 μg/cm2 have been produced.

    Download full text (pdf)
    FULLTEXT01
  • 90.
    Berlind, Torun
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Pribi, G. K.
    J. A. Woollam Co Inc., Lincoln, NE, USA.
    Thompson, D.
    Department of Electrical Engineering, University of Nebraska-Lincoln, NE, USA.
    Woollam, J. O.
    J. A. Woollam Co Inc., Lincoln, NE, USA.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Effects of ion concentration on refractive indices offluids measured by the minimum deviation technique2008In: Physica Status Solidi. C, Current topics in solid state physics, ISSN 1610-1634, E-ISSN 1610-1642, Vol. 5, no 5, p. 1249-1252Article in journal (Refereed)
    Abstract [en]

    The prism minimum deviation technique has been used to measure the fluid dependence of refractive indices. Fluids with varying ion concentration (0 to 1.0 M) and varying protein concentration (0.01-10 mg/ml) have been examined and the measurements show that these parameters influence the refractive index values. Also it is shown by simulations that it is important to take the change of refractive index of the fluid into account when evaluating insitu protein adsorption measurements.

  • 91.
    Berlind, Torun
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Pribil, G.
    Thompson, D.
    Woollam, J.A.
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Effects of Ion Concentration on Refractive Indices of Fluids Measured by the Minimum Deviation Technique2006In: Optikdagen 2006,2006, 2006Conference paper (Other academic)
    Abstract [en]

      

  • 92.
    Berlind, Torun
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Pribil, G.K.
    J.A. Woollam Co, USA.
    Thompson, Daniel W.
    Dept. of Electrical Engineering and Center for Materials Research and Analysis University of Nebraska - Lincoln.
    Woollam, John A.
    J.A. Woollam Co, USA.
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Effects of Ion Concentration on Refractive Indices of Fluids Measured by the Minimum Deviation Technique2007In: 4th International Conference on Spectroscopic Ellipsometry,2007, Linköping: Linköpings universitet , 2007, p. 141-Conference paper (Refereed)
  • 93.
    Berlind, Torun
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Tengvall, Pentti
    Department of Biomaterials, Institute of Surgical Sciences, The Sahlgrenska Academy, University of Gothenburg.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Protein adsorption on thin films of carbon and carbon nitride monitored with in situ ellipsometry2011In: ACTA BIOMATERIALIA, ISSN 1742-7061, Vol. 7, no 3, p. 1369-1378Article in journal (Refereed)
    Abstract [en]

    Amorphous carbon and amorphous, graphitic and fullerene-like carbon nitride thin filmswere deposited by reactive magnetron sputtering and optically characterized withspectroscopic ellipsometry. The films were exposed to human serum albumin and theadsorption was monitored in situ using dynamic ellipsometry. From the ellipsometric data theadsorbed amount of proteins was quantified in terms of surface mass density using de Feijter'smodel. The results indicated larger adsorption of proteins onto the amorphous films comparedto the films with a more ordered microstructure. Complementary studies with labeled HSAusing radioimmunoassay showed up to 6 times higher protein adsorption compared to theellipsometry measurement which partly might be explained by differences in surfaceroughness (from 0.3 to 13 nm) among the films. The elutability of adsorbed labeled HSAusing unlabeled HSA and sodium dodecyl sulphate was low compared to a silicon reference.In addition, the four types of films were incubated in blood plasma followed by antifibrinogen,anti-HMWK or anti-C3c revealing the materials response to complement andcontact activation. Three of the films indicated immunoactivity, whereas the amorphouscarbon showed less immunoactivity compared to a titanium reference. All films showedindications of a stronger ability to initiate the intrinsic pathway of coagulation, compared tothe reference. Finally, the surfaces bone bonding ability was investigated by examination oftheir ability to form calcium phosphate (CaP) crystals in a simulated body fluid, with a-CNxdepositing most CaP after 21 days of incubation.

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    fulltext
  • 94.
    Boulenguez, Julie
    et al.
    INSP - CNRS Paris 6 and 7 Universities.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Järrendahl, Kenneth
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Berthier, Serge
    INSP - CNRS Paris 6 and 7 Universities.
    Ellipsometric study of photonic structures in wing scales of butterflies2007In: 4th International Conference on Spectroscopic Ellipsometry, 2007, 2007, p. 309-Conference paper (Other academic)
    Abstract [en]

    In this report the possibility to explore the polarization properties of the wing scales of Morpho butterflies using spectroscopic ellipsometry is presented. Measurements were performed on the dorsal sides of three species of the Morpho family, rhetenor, menelaus and sulkowskyi, to compare the polarization properties of nanostructures in the wings. In these species colouration changes under polarized light were observed and all the wing scales are flat. Their photonic structures have the same general shape; they dier, mainly in terms of size and number of layers. The instrument used is a double rotating compensator ellip- someter working in the spectral range 245 nm-1700 nm. This type of instrument can measure the Mueller matrix of a sample. The Morpho rhetenor geometrical structure is known from scanning electron micrographs. Based on this structure, a Bruggeman eective

  • 95. Broitman, E.
    et al.
    Hellgren, N.
    Wanstrand, O.
    Wänstrand, O., Department of Materials Science, Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden.
    Johansson, M.P.
    Berlind, Torun
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Sjostrom, H.
    Sjöström, H., Sjöstrom Coating Consulting, KarlGustavsgatan 21A, SE-411 20 Göteborg, Sweden.
    Sundgren, J.-E.
    Office of the President, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
    Larsson, M.
    Department of Materials Science, Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden.
    Hultman, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics.
    Mechanical and tribological properties of CNx films deposited by reactive magnetron sputtering2001In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 248, no 1-2, p. 55-64Article in journal (Refereed)
    Abstract [en]

    The hardness, elasticity, wear rate and friction coefficient of carbon nitride (CNx) films of defined microstructure and composition are presented. CNx films were deposited by dc reactive magnetron sputtering from a C target in N2/Ar plasma. Films were grown on Si (001), Ni, and HSS substrates to thickness of ~0.5 µm at a total pressure of 3 mTorr with the N2 fraction varied from 0 to 1, and the substrate temperature Ts, varied from ambient to 350°C. The mechanical and tribological properties of the coatings were evaluated by nanoindentation and dry ball-on-disk test. For CNx (0 = x = 0.35) films deposited below 200°C (amorphous structure), the elastic recovery and hardness do not change significantly with increasing N concentration, however, the friction coefficient increases from 0.19 to 0.45, while the coating wear rate is low. For CNx (0 = x = 0.15) films grown at Ts = 350°C, where a transition from a graphite-like to a "fullerene-like" phase occurs, a dramatic increase in hardness and elasticity is observed. Furthermore, the rms surface roughness decreases from 15.0 to 0.4 nm. For 0.15 = x = 0.20, CNx films deposited at Ts = 350°C (fullerene-like phase) exhibit a smooth surface, high hardness and elasticity (~90% recovery), and a coefficient of friction against hard steel of ~0.25. For all substrates, film friction coefficient tends to increase as the nitrogen content in the film is increased. Results also indicate the formation of a transfer layer which improves the tribological properties of the films. © 2001 Elsevier Science B.V. All rights reserved.

  • 96.
    Bukaluk, A.
    et al.
    Instytut Matematyki I Fizyki, Akademia Techniczno-Rolnicza, Ul. K., Bydgoszcz, Poland.
    Wronkowska, A.A.
    Instytut Matematyki I Fizyki, Akademia Techniczno-Rolnicza, Ul. K., Bydgoszcz, Poland.
    Wronkowski, A.
    Instytut Matematyki I Fizyki, Akademia Techniczno-Rolnicza, Ul. K., Bydgoszcz, Poland.
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Firszt, F.
    Instytut Fizyki, Uniw. Mikolaja Kopernika, Ul. G., Torun, Poland.
    Legowski, S.
    Instytut Fizyki, Uniw. Mikolaja Kopernika, Ul. G., Torun, Poland.
    Meczynska, H.
    Meczynska, H., Instytut Fizyki, Uniw. Mikolaja Kopernika, Ul. G., Torun, Poland.
    Szatkowski, J.
    Instytut Fizyki, Uniw. Mikolaja Kopernika, Ul. G., Torun, Poland.
    Auger electron spectroscopy, ellipsometry and photoluminescence investigations of Zn1-XBeXSe alloys2001In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 175-176, p. 531-537Article in journal (Refereed)
    Abstract [en]

    In this paper, properties of the Zn1-XBeXSe crystals grown from the melt by the high-pressure Bridgman method are reported. Spectroscopic ellipsometry has been used for determination of the complex dielectric function of Zn1-XBeXSe. On the basis of the photon energy dependence of the dielectric function, the energy gaps of alloys containing different beryllium concentrations have been evaluated. Measurements of the photoluminescence (PL) spectra allowed to find the excitonic gap in the investigated alloys. Auger electron spectroscopy (AES) with simultaneous argon ion sputtering has been used for determination of surface composition. AES investigations allowed to make predictions concerning distribution of particular elements in the samples. © 2001 Elsevier Science B.V.

  • 97.
    Buyanova, Irina
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Functional Electronic Materials.
    Izadifard, Morteza
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Kasic, A.
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics.
    Chen, Weimin
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Functional Electronic Materials.
    Xin, H. P.
    Hong, Y. G.
    Tu, C. W.
    Analysis of band anticrossing in GaNxP1-x alloys2004In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 70, p. 085209-Article in journal (Refereed)
    Abstract [en]

     Temperature-dependent absorption, photoluminescence excitation, and spectroscopic ellipsometry measurements are employed to accurately determine compositional and temperature dependences of the conduction band (CB) states in GaNP alloys. The CB edge and the higher lying Γc CB minimum (CBM) are shown to exhibit an apparently anticrossing behavior, i.e., the N-induced redshift of the bandgap energy is accompanied by a matching blueshift of the Γc CBM. The obtained data can be phenomenologically described by the band anticrossing model. By considering strong temperature dependence of the energy of the interacting N level, which has largely been overlooked in earlier studies of GaNP, the interacting N level can be attributed to the isolated substitutional NP and the coupling parameter is accurately determined.

  • 98.
    Buyanova, Irina
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Materials Science .
    Izadifard, Morteza
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Kasic, A.
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Chen, Weimin
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Materials Science .
    Xin, H.P.
    Hong, Y.G.
    Tu, C.W.
    Compositional Dependence of conduction band states in GaNP alloys2004In: 5th International Conference on Low Dimensional Structures and Devices,2004, 2004, p. 64-Conference paper (Other academic)
  • 99.
    Campoy-Quiles, M.
    et al.
    Experimental Solid State Physics Group, Blackett Laboratory, Imperial College London, UK.
    Nelson, J.
    Experimental Solid State Physics Group, Blackett Laboratory, Imperial College London, UK.
    Etchegoin, P.G.
    Experimental Solid State Physics Group, Blackett Laboratory, Imperial College London, UK.
    Bradley, D.D.C.
    Experimental Solid State Physics Group, Blackett Laboratory, Imperial College, UK.
    Zhokhavets, V
    Inst of Physics, Ilmenau Technical University, Germany.
    Gobsch, G.
    Inst of Physics, Ilmenau Technical University, Germany.
    Vaughan, H.
    Dept of Physics University of Durham, UK.
    Monkman, A,
    Dept of Physics, University of Durham, UK.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Persson, Nils-Krister
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, The Institute of Technology.
    Garriga, M.
    Inst de Ciència de Materials de Barcelona - CSIS, Campus de la UAB, Spain.
    Alonso, M.I.
    Inst de Ciència de Materials de Barcelona - CSIS, Campus de la UAB, Spain.
    Herrmann, G.
    Max Planck Institute for Polymer Research, Germany.
    Becker, M.
    Max Planck Institute for Polymer Research, Germany.
    Scholdei, W.
    Max Planck Institute for Polymer Research, Germany.
    Jahja, M.
    Max Planck Institute for Polymer Research, Germany.
    Bubeck, C.
    Max Planck Institute for Polymer Research, Germany.
    On the determination of anistropy in polymer thin films: A comparative study of optical techniques2008In: Physica Status Solidi. C: Current Topics in Solid State Physics, ISSN 1862-6351, Vol. 5, no 5, p. 1270-1273Article in journal (Refereed)
    Abstract [en]

    We have used seven different techniques to measure the anisotropic refractive index of poly(vinylcarbazole) films. These techniques are: two types of variable angle spectroscopic ellipsometry (VASE) with multiple sample analysis, Interference enhanced VASE, Transmittance combined with VASE, Polarised Reflectance, beta-scan VASE, and prism coupling. We have found the average ordinary and extraordinary indices at 633 nm to be no = nTE = 1.675 ± 0.008, and ne = nTM = 1.722 ± 0.018, respectively, consistent amongst methods and conclusive on the magnitude of Δn in polymer films.

  • 100. Chen, Jiaxin
    et al.
    Obitz, C
    Arwin, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, Faculty of Science & Engineering.
    Forssgren, B
    CORROSION KINETICS OF NICKEL-BASE ALLOYS WITH HIGH CHROMIUM CONTENTS UNDER SIMULATED BWR NORMAL WATER CHEMISTRY CONDITIONS AND HIGH FLOW VELOCITY2015Conference paper (Refereed)
    Abstract [en]

    In light water reactors corrosion-induced material degradation is a critical issue not only for material integrity but also for plant radiation field build-up. In BWRs nickel-base alloys, such as Alloy 600, Alloy 82 and Alloy 182, are applied in various parts of reactor components including welds. However, their corrosion mechanisms are not very well understood. Although the complex compositions of different nickel-base alloys generally prohibit us to single out some specific alloy constituent having a major impact on alloy corrosion rate, a higher chromium content is often thought to be beneficial to forming a more protective oxide film against corrosion attack. In this paper we report a corrosion kinetics study on high chromium nickel-base alloy welding consumables, Alloy 52M and Alloy 152, under simulated BWR normal water chemistry conditions and high flow velocity for up to nine weeks exposure. The corrosion rates are derived from measurements of weight losses of test coupons, oxide thicknesses with infrared ellipsometry, and microstructures of oxide films with electron microscopy. The obtained corrosion rates are then compared to that for Alloy 182, Alloy 82 and Alloy 600. The results show that the corrosion rate for Alloy 52M is similar to those for Alloy 182, whereas the rate for Alloy 152 is reduced to less than half. These observations indicate that the corrosion kinetics for nickel-base alloys is complex and alloy chromium content alone is not a dominant factor in influencing alloy corrosion rate.

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