Physical and Optical Properties of Poly(3-AlkylThiophene) with a View to the Fabrication of a Highly Nonlinear Waveguide

Publisher: Bentham (ISSN: 1874-088X)International audienceIn order to take advantage of the very high nonlinear susceptibility of conjugated polymer materials, Poly(3-AlkylThiophene)s, P3AT, were synthesized in the laboratory. The physical, thermomechanical and linear optical propertiesof synthesized P3AT have been investigated and the first experimental attempts at creating nonlinear optical waveguides and determining their characteristics are presented. After synthesizing P3AT, the relationships between polymer chain characteristics and mechanical properties are investigated to see if the polymer is suitable for optical waveguide process technology. We also examine the optical attenuation of the synthesized material, a crucial factor in anticipating the relative opacity of the future component. For the first time we present the absorption spectrum of 3-Octylthiophenemolecules in the Near Infra-Red (NIR) region that suggests optical losses for the material are about 0.6 dB.cm-1 at 1550 nm. Next we examined several waveguide structures such as ridge, buried and Strip Loaded WaveGuides (SLWG) based on P3AT material. For the buried waveguides, we have observed the signal transmission and in our opinion the low optical transmission of P3AT ridge and SLWG could be attributed to extrinsic losses (mainly scattering) due to both the remaining insoluble products in the polymer and to the poor adhesion between optical layers

Enhanced control of plasma etching parameters by optical emission spectroscopy

International audienceLaser interferometry and optical emission spectroscopy are well known techniques to characterize thin film etching during plasma processes. On one hand, laser interferometry allows the detection of end point and in situ etching rate, however it supposes using an external laser source. On the other hand, optical emission spectroscopy is useful for end point detection and also gives information on the plasma composition, if it works in a sufficient range of wavelength (for example 400-800 nm in our case) to find the characteristics plasma emission lines. As a result, this technique could also enable us to determine the etching rate in real time. The main topic of this paper is to show that, in a specific etching condition and geometrical configuration with the appropriated materials, Optical Emission Spectroscopy can gather the advantages of the two diagnostic techniques. This will be study on O2 etching plasma dedicated to polymers patterning in an optical integrated circuit process

Some features of optical waveguide realization in polymer for large scale circuit integration

International audienceWith a view to improving the realisation of polymer optical waveguide some features relevant to the photolithography process are analysed. This paper focuses on defects that occur on the surface of polymer layers involved in the process. For example, depending on the heat treatment or the deposited material, some worm-like defects appear on the polymer surface. When they occur, the waveguide surface roughness becomes too high (about one hundred nm and more). This means that the optical performance of the waveguides is too poor. In this document, we show the changes in temperature on polymer film surfaces which are coated with a thin inorganic layer and the occurrence of these defects is observed. This work confirms that the defect occurrence is clearly linked to the glass transition temperature. The paper reports that, in some cases, the adjustment of thermal properties by annealing can advantageously shift the glass transition, without changing the target optical properties

Polymer optical circuits technology for large-scale integration of passive functions

Conference 6183 "Integrated Optics, Silicon Photonics, and Photonic Integrated Circuits", poster session [6183-54], proceedings of SPIE (ISBN 9780819462398)International audiencePolymers are attractive to realize integrated circuits specially because they are very simple to process and are promising for low cost devices. Moreover, beside low cost technology, the large possible range of refractive index, could lead to large scale of integration, lowering the fabrication costs. In some cases, it could be an alternative solution to semiconductor or inorganic dielectric technologies. With usual UV photolithography technology, this work shows that it is possible to perform small guides in order to provide relatively high circuit densification. The refractive index contrast, between optical core and cladding, can be as high as 0.07 instead of 0.02 for the higher contrast in silica Ge doped waveguides. Recently, this contrast has been increased to 0.11 at the wavelength of 1550nm. These materials make possible the patterning of guides having radius of curvature smaller than 200μm. Such curvatures open the way to functions based on microrings that potentially lead to compact wavelength multiplexers. With the view to control the fabrication of polymer waveguides, some features of the process are reported here. For example, shortcomings such as unsuitable film worm aspects are described and solutions are given with requirements assigned to rough materials. Mechanical and thermal properties of polymers have to be adjusted to withstand integrated circuit processing. This paper also presents results concerning the realization of integrated passive microring resonators with this technology

Strengthened polymethacrylate materials for optical waveguides and integrated functions

International audienceWe studied the property adjustments of polymers such as PMMA poly(methylmethacrylate) and PMMI poly(methylmethacrylimide) for optical waveguide applications. The standard generic process to yield ridge waveguides requires the PMMA to undergo thermal treatment to avoid worm-like defects. We analysed the occurrence of these defects and found a solution to make the PMMA strengthened to pass the whole process. Then, the optical losses of both the polymers are investigated at two wavelengths and with two methods. Finally, small singlemode ridge waveguides are produced with mode diameters around 3-4 μm and linear optical losses ~1-3 dB/cm at 1550 nm. The index contrast is sufficiently high to perform, for example, wavelength micro-ring resonators based filters

Investigation on optical waveguide realisations based on polymers with large third order non-linear susceptibility

conference 6999 « Organic Optoelectronics and Photonics », poster session [6999-67], http://spie.org/x24034.xmlInternational audienceConjugated polymer materials have great potential to be suitable candidates for use in all-optical network communications. They possess ultra-fast response times and a large third order non-linearity compared to minerals (third order susceptibility Χ(3) of conjugated polymers can be 4 orders of magnitude larger than that of fused silica). Such large non-linearities would allow the fabrication of compact all-optical devices at low power levels. Here we present the first investigations into the creation of a conjugated polymer single mode optical waveguide based on Poly(3- AlkylThiophene) (P3AT). We first synthesized the P3AT and tried to control the chemical reaction conditions in order to improve polymer solubility in common organic solvents. In parallel, we studied the engineering of P3AT single mode waveguide structures made by photolithography techniques which requires the adjustment of P3AT thermo-mechanical properties. Recently, we have been able to fabricate and measure the parameters of Strip-Loaded and buried waveguides with usual polymers. We intend to adapt these processes to obtain the first P3AT single mode optical waveguide

Wide tunable thermo-optical filters with polymer micro-ring resonators

conference 6996 " Silicon Photonics and Photonic Integrated Circuits ", poster session, [6996-63], http://spie.org/x24034.xmlInternational audiencePolymers are increasingly attractive for the creation of optical integrated circuits particularly owing to a high thermo-optical coefficient (-10-4 °C-1) which allows to design optical functions tunable according to temperature. For example, tunable filters or multiplexers are attractive in telecom applications for bringing broadband services to subscribers. Moreover, the large available range of refractive index, leads to large scale of integration, lowering the fabrication costs and could be an alternative solution to semiconductor or inorganic dielectric technologies. In this work, optical functions were created using standard photolithography and Reactive Ion Etching (RIE). Photolithography was used with particular conditions to improve pattern resolution. Firstly, the details of making optical polymer waveguides and wavelength micro-ring based filters are given. Optical loss measurements of waveguides and optical characterisation of micro-ring resonators are also shown for which the results are in agreement with the modelling. Secondly, the same micro-ring resonators were observed with the temperature change and we noticed that the variation of resonance wavelength is about 0.2 nm.°C-1. This is just what is needed for the creation of tunable filters or multiplexers without electrical high power, considering the very small size of the component

Optique intégrée en polymère pour micro multiplexeur

JNOG Thème 1 " optique guidée planaire (structures actives et passives) " [JNOG1_1], recueil des communications p.391-393, http://www.univ-savoie.fr/labos/lahc/horizonsjnog/download/Actes_Horizons_JNOG_2005.pdfNational audienceNous montrons ici la possibilité de réaliser des fonctions optiques intégrées passives miniaturisées en technologie Polymère. Par ailleurs, l'accent est mis sur la mesure des pertes optiques et sur la réalisation de micro-résonateurs intégrés en anneaux

Intérêt des « Strip Loaded Waveguides » pour la réalisation de guides polymères à fort ki(3)

session Affiches [P68]National audienceLe présent article montre comment une technologie de guidage optique induit par un ruban, les "Strip Loaded WaveGuides", permet de réaliser des guides optiques polymères avec des matériaux difficiles à structurer par les techniques habituelles. Dans un premier temps, nous validons expérimentalement le concept à l'aide de polymères conventionnels et nous mettons en évidence les paramètres permettant d'induire dans une couche de matériau un guidage monomodal avec un confinement de lumière sufffisant. puis nous montrons comment tirer avantage de ce procédé pour réaliser des guides en poly(3-alkylthiophène) autrement que par une techniologie "ridge"

Vers la réalisation de guides en polymères à fort ki(3)

session Affiches, thème 5 « Optique intégrée passive et active » [A-Th5-13]National audienceCette communication présente les premiers travaux concernant la réalisation de guides monomodes en polymères par la technologie de photolithographie indirecte et de gravure plasma. Pour minimiser les difficultés technologiques, le choix s'est porté d'abord sur les poly(alkylthiophène)s. Nous rapportons ici les performances publiées en terme de Χ(3) du matériau ainsi que les premiers essais de réalisation de guides au laboratoire. Ceci est entrepris en vue de réaliser par la suite une porte optique ultre-rapide (~ps)