Z-scan measurements of the nonlinear absorption and refractive index for fluorescein 548-doped organically modified sol–gel silica films

2001 ◽  
Vol 18 (2) ◽  
pp. 235-241 ◽  
Author(s):  
S.K Lam ◽  
M.A Chan ◽  
D Lo
Keyword(s):  
Refractive Index ◽  
Nonlinear Absorption ◽  
Sol Gel ◽  
Silica Films ◽  
Organically Modified

Heat treatment of spun-on acid-catalyzed sol-gel silica films

1994 ◽  
Vol 9 (3) ◽  
pp. 723-730 ◽  
Author(s):  
T.M. Parrill
Keyword(s):  
Heat Treatment ◽  
Refractive Index ◽  
Spin Coating ◽  
Compressive Strain ◽  
Sol Gel ◽  
Silica Films ◽  
Si Substrates ◽  
Acid Catalyzed ◽  
Film Porosity

SiO2 films, formed by spin coating acid-catalyzed TEOS-based sol-gel on Si substrates, were annealed at 300–1000 °C and analyzed using ellipsometry, FTIR, and in situ stress measurements. Film porosity ranged from an average of 28% before annealing to 7% after annealing 3 h at 1000 °C. Below ≍800 °C, water and silanol removal caused a decrease in refractive index and increase in the in-plane tensile stress. Infrared spectra indicated compressive strain normal to the plane, however. Above ≍800 °C, further densification and structural relaxation occurred. Exposure to H2O also caused relaxation after annealing, as the most compressed Si–O–Si units reacted preferentially with moisture.

A novel route to control refractive index of sol-gel derived nano-porous silica films used as broadband antireflective coatings

2000 ◽  
Vol 78 (2-3) ◽  
pp. 135-139 ◽  
Author(s):  
Guangming Wu ◽  
Jue Wang ◽  
Jun Shen ◽  
Tianhe Yang ◽  
Qinyuan Zhang ◽  
...  
Keyword(s):  
Refractive Index ◽  
Sol Gel ◽  
Porous Silica ◽  
Antireflective Coatings ◽  
Silica Films

Microstructural characterization of sol-gel coating on PET films

1994 ◽  
Vol 52 ◽  
pp. 886-887
Author(s):  
R. T. Chen ◽  
R.A. Norwood
Keyword(s):  
Ion Beam ◽  
Sol Gel ◽  
Industrial Applications ◽  
Hard Coatings ◽  
Nanometer Scale ◽  
Ion Beam Sputtering ◽  
Process Technology ◽  
Refractive Index Measurement ◽  
Organically Modified ◽  
Pet Films

Sol-gel processing has been used to control the structure of a material on a nanometer scale in preparing advanced ceramics and glasses. Film coating using the sol-gel process was also found to be a viable process technology in applications such as optical, porous, antireflection and hard coatings. In this study, organically modified silicate (Ormosil) coatings are applied to PET films for various industrial applications. Sol-gel materials are known to exhibit nanometer scale structures which havepreviously been characterized by small-angle X-ray scattering (SAXS), neutron scattering and light scattering. Imaging of the ultrafine sol-gel structures has also been performed using an ultrahigh resolution replica/TEM technique. The objective of this study was to evaluate the ultrafine structures inthe sol gel coatings using a direct imaging technique: atomic force microscopy (AFM). In addition, correlation of microstructures with processing parameters, coating density and other physical properties will be discussed.The materials evaluated are organically modified silicate coatings on PET film substrates. Refractive index measurement by the prism coupling method was used to assess density of the sol-gel coating.AFM imaging was performed on a Nanoscope III AFM (by Digital Instruments) using constant force mode. Solgel coating samples coated with a thin layer of Ft (by ion beam sputtering) were also examined by STM in order to confirm the structures observed in the contact type AFM. In addition, to compare the previous results, sol-gel powder samples were also prepared by ultrasonication followed by Pt/Au shadowing and examined using a JEOL 100CX TEM.

Nanostructured Doped Silica Films Application as Sensitive Layers for Chemical Sensors

2013 ◽  
Vol 684 ◽  
pp. 7-11
Author(s):  
Sergey Krutovertsev ◽  
Alla Tarasova ◽  
Olga Ivanova ◽  
Larisa Krutovertseva
Keyword(s):  
Initial Conditions ◽  
Sol Gel ◽  
Silica Films ◽  
Adsorption Activity ◽  
Developed Surface ◽  
Sol Gel Process ◽  
Sensitive Characteristics ◽  
The Right ◽  
Kinetics Of ◽  
Matrix Factors

The sensor behavior of nanostructured doped silica films produced by sol-gel way were examined. Hygroscopic substances and polyoxometalates were used as additives to make more significant sensitive characteristics of initial matrix. Factors that have effect on sol preparation and films forming were investigated. Adsorption activity of the sensitive films was studied and it was shown that the films had a highly developed surface with nano-size pores. Change of initial conditions of sol-gel process gives opportunity to influence on kinetics of gel formation and consequently, on structure and properties of final materials. The study showed that the conditions of the environment affected the sensors characteristics markedly, which can be improved by choosing of the right procedure of forming and treatment. Influence of type and additive substances quantity into doped films was discussed in the paper

Sol-gel process of non-linear optical silica films with organic chromophore as side chain

1996 ◽  
Vol 31 (9) ◽  
pp. 2443-2446 ◽  
Author(s):  
Po-Hou Sung ◽  
Shao-Ling Wu ◽  
Chien-Yang Lin
Keyword(s):  
Sol Gel ◽  
Side Chain ◽  
Silica Films ◽  
Sol Gel Process ◽  
Non Linear ◽  
Linear Optical ◽  
Organic Chromophore

Sol–gel derived mesoporous silica films using amphiphilic triblock copolymers

2003 ◽  
Vol 332 (1-3) ◽  
pp. 199-206 ◽  
Author(s):  
Nobuaki Kitazawa ◽  
Hideyoshi Namba ◽  
Masami Aono ◽  
Yoshihisa Watanabe
Keyword(s):  
Mesoporous Silica ◽  
Triblock Copolymers ◽  
Sol Gel ◽  
Silica Films

Preparation of Porous Organically-Modified Silicate Hybrids for Cell Culture Matrix

2007 ◽  
Vol 330-332 ◽  
pp. 1177-1180 ◽  
Author(s):  
Kanji Tsuru ◽  
Satoshi Hayakawa ◽  
Yuki Shirosaki ◽  
T. Okayama ◽  
K. Kataoka ◽  
...  
Keyword(s):  
Cell Culture ◽  
Mammalian Cells ◽  
Pore Diameter ◽  
Sol Gel ◽  
Three Dimensional ◽  
Culture Methods ◽  
Organically Modified ◽  
Dimensional Cell

Porous & rubbery organic-inorganic hybrids were synthesized from tetraethoxysilane (TEOS) and polydimethylsiloxane (PDMS) through a sol-gel route using sieved sucrose granules as a porogen. The porous hybrids with a high content of PDMS behaved like polymer sponge. The porosity was over 90% irrespective of the hybrid composition and the pore diameter ranged from 100 to 500 μm. In the three-dimensional cell culture, mammalian cells were well cultured in the porous hybrids. The present results indicate that the hybrids may be a promising scaffold for developing such functional culture methods.

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