1. Jaglarz1, K. Marszalek2 B. Jarzabek3, R. Duraj4 and I. Noor5 AK Arof5 N. Wolska6 and B. Sahraoui7

1,6Cracow University of Technology, Faculty of Mechanics M2, Al. Jana Pawła I37,31-864 Cracow, Poland

2AGH University of Science and Technology, Mickiewicza av.30, 30-059 Cracow, Poland

3Institute of Physics, Cracow University of Technology, ul. Podchorazych 1,  30‑084 Cracow, Poland

4Centre of Polimer Material PAN 41-819 Zabrze ul. M. Curie-Skłodowskiej 34 Poland

5University of  Malaya, Ionic center, Dept Phys, Dept Phys, Kuala Lumpur 50603, Malaysia

6Elkom Trade S. A. Targowa 21 street, 27-400 Ostrowiec Świętokrzyski

7LUNAM Université, Université d’Angers, CNRS UMR 6200, Laboratoire MOLTECH-Anjou, 2 bd Lavoisier, 49045 Angers cedex, France

Abstract

Thin polymer films are currently under intensive investigation owing to their promising optical and electrical properties. The roughness and refractive index variation in a film, and also  presence of unwanted molecular inclusions  in bulk created during film formation may lead to incoherent light scattering. Therefore the analysis of thin film optical spectra becomes more complicated. The aim of this work is presentation of light scattering phenomena occurring in polymer layer. They can be described by the Fresnel model for specular reflectance and as well Rayleigh,  Debye and scalar theories of light scattering for non-directional reflection from a diffusive film. Furthermore, the optical methods based on combined spectro-goniometric measurements have been presented.

These investigations allow determining many important parameters as: optical constants, films thickness and their surface roughness and also optical scattering coefficients diffusive layers.

Keywords: elastic light scattering, spectroscopic ellipsometry diffusive reflectance and transmittance

  1. Introduction

The description of optical phenomena in most thin film in general is commonly limited to presentation of interference effect occurring in layers [1,2]. Using Fresnel theory we are able to determine film thickness and as well their optical constants. In these studies one utilizes specular parts of reflected from or transmitted by film. The complex refractive index and film thickness of thin films may be effectively determined by the use of ellipsometric method [3]. Ellipsometry uses the light of known polarization incident on the studied film and detects the polarization state of the reflected light. Incident light is usually linearly polarized and the reflected light has elliptical polarization. Spectroscopic ellipsometry directly determines two angles Ψ and Δ, with:

image001                                                          (1)

where Ψ represents the angle determined from the amplitude ratio between p- and s- polarizations and Δ is the phase shift between the polarized waves. rp and rs are the complex Fresnel reflection coefficients for p- and s- polarizations, respectively. Knowledge of ellipsometric angles allows us to determine dispersion of the refractive index n and the extinction coefficient k of the films.

The ellipsometry may be applied when most of reflected and transmitted radiation is coherent. Such condition is done in broad variety of homogenous flat layers, typical in inorganic coatings. In polymer films one may appear other phenomena related to non-coherent and non-specular light scattering. They result mostly from variation of refractive index in bulk material. It may result from non-regular distribution of polymer chains in films [4, 5]. As well in the layer may occur small scattering centers responsible for Rayleigh scattering. As representative samples in order to demonstrate light scattering phenomena the polyazomethine (PPI) thin films have been chosen. The PPI layers are important materials to obtain organic LED’s devices [6].

...czytaj dalej Elastic scattering phenomena in thin polymer layers

  1. Karakayaa, A. Karakasb, M. Taserb, N. Wolskac, AK Arofd and B. Sahraouie

 

aDepartment of Energy Systems, Faculty of Engineering & Architecture, Sinop University, Sinop 57000, Turkey

bSelcuk University, Faculty of Sciences, Department of Physics, Campus 42049, Konya, Turkey

cElkom Trade S. A. Targowa 21 street, 27-400 Ostrowiec Świętokrzyski; and Mechanical Department, Cracow Uniwersity of Technology, Jana Pawla II 37 street, 31-867 Cracow, Poalnd

dUniversity of Malaya, Ionic center ,Physics Dept, Kuala Lumpur 50603, Malaysia

eLUNAM Université, Université d’Angers, CNRS UMR 6200, Laboratoire MOLTECH-Anjou, 2 bd Lavoisier, 49045 Angers cedex, France

Abstract

Due to the connecting one π-conjugated group with the two backside donor and acceptor groups, anionic 3-dicyanomethylen-5,5-dimethyle-1-[2-(4-hydroxyphenyl)ethenyl)]-cyclohexene (1) might possess nonlinear optical (NLO) properties. To estimate the potential for second-order NLO behaviour; the electric dipole moments (µ) and dispersion-free dipole polarizabilities (α) and first hyperpolarizabilities (β) have been determined by density functional theory (DFT) at B3LYP/6-31++G(d, p) level. Quantum mechanical calculations using time-dependent Hartree-Fock (TDHF) procedure have been utilized to evaluate frequency-dependent α, β and second-order susceptibilities (χ(2)) of 1. The one-photon absorption (OPA) characterization of 1 has been theoretically obtained by means of configuration interaction (CI) with 6-31G basis set. Our theoretical results on the maximum OPA wavelength, second-order susceptibilities and corresponding microscopic NLO responses are accorded with the previous experimental observations of the investigated compound. The highest occupied molecular orbitals (HOMO), the lowest unoccupied molecular orbitals (LUMO) and the HOMO-LUMO band gaps for 1 have been also examined by DFT/B3LYP method.

Keywords: First hyperpolarizability; dipole polarizability; second-order susceptibility; one-photon absorption; time-dependent Hartree-Fock; density functional theory.     

...czytaj dalej Computations of second-order hyperpolarizabilities and susceptibilities and comparisons with corresponding experimental data of anionic 3-dicyanomethylen-5,5-dimethyle-1-[2-(4- hydroxyphenyl)ethenyl)]-cyclohexene

Natalia Wolska*1,2

Janusz Jaglarz*2

Janusz Szewczenko*3

*Corresponding author: nwolska@elkomtrade.eu
1 Elkom Trade S.A., ul. Targowa 21, 27-400 Ostrowiec Świętokrzyski, Poland

2 Cracow University of Technology, Faculty of Mechanics M2, Al. Jana Pawła II 37, 31-864 Cracow, Poland
3Department of Biomaterials and Medical Devices Engineering, Faculty of Biomedical Engineering, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland

Niestandardowe metody optyczne w badaniach powierzchni elektrochemicznie spasywowanego stopu Ti6Al7Nb.

Celem pracy jest przedstawienie możliwości zastosowania metod optycznychdo wyznaczenia parametrów topograficznych powierzchni stopu Ti przed i po procesie pasywacji, jak również określenie wpływu wstępnych obróbek modyfikujących powierzchnie stopu na grubość tworzonych warstw pasywnych. Zastosowana w niniejszej pracy metodyka pomiarowa, wykorzystująca klasyczne i niestandardowe techniki badań optycznych, pozwoliła na wyznaczenie grubości warstw, chropowatość, długość autokorelacyjną i inne parametry statystyczne opisujące topografię powierzchni. Zaletą przedstawionychniestandardowych technik jest ich nie-inwazyjność i bezkontaktowość.

 

Non-standard optical techniques used in the studies of electrochemically passivated Ti6Al7Nb alloy.

The aim of this work is presentation of optical techniques applied for the measurements of topographic parameters of Tialloy before and after itspassivation, as well as determination of the influence of pre-treatment methods on the thickness of passive films. The applied methodology is non destructive and it includes standard and non-standard optical techniques to determine the thickness, roughness, autocorrelation length and other statistic parameters of film. Advantage of presented non-standard techniques is their non-destructive and non-invasive character.

...czytaj dalej Niestandardowe metody optyczne w badaniach powierzchni elektrochemicznie spasywowanego stopu Ti6Al7Nb.

1

Konstanty Marszałek1, Natalia Wolska2 Janusz Jaglarz2

2AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Cracow

Cracow University of Technology, Faculty of Mechanics M2, Al. Jana Pawła I37,31-864 Cracow, Poland

Abstract:

The work presents an employment of two scanning optical techniques i.e. optical profilometry (OP) and angle resolved scattering (ARS) method. The first measures the reflected light from a film scanned upon the surface, while the seconds takes light intensity upon the angle of scattered radiation. The ARS and OP studies, being complementary to the atomic force microscopy (AFM) allow to get information about  surface topography.  Scattered radiation measured by ARS and  OP is a function of heights and slopes of microfacets. The analysis of images allows to determine the most important statistic surface parameters, like roughness, height distribution and autocorrelation length, in long spatial wavelength range by the determination of power spectral density (PSD) function. The fast Fourier transform  (FFT) of ARS and OP images allow to find the distribution of surface features in the inverse space, such as periodicity and  anisotropy. In this paper  the results obtained for  porous SiO2,  SiO2-TiO2, blends, TiN and polymer thin films  have been presented. The paper demonstrates the usefulness of the ARS and optical profilometry for the surface and volume thin film inspection.

PACS Index: 78.35+c, 78.68+m, 78.66.Jg

...czytaj dalej Angle resolved scattering combined with optical profilometry as tools in thin films and surface survey