Preparation of MgF^2-SiO^2 Thin Films with Low Refractive Index by Sol-gel Process

ABSTRACTLead lanthanum titanate thin films have been prepared on MgO and sapphire substrates by sol-gel method. XRD analyses confirm that the PLT films fabricated on MgO(lOO) and c-plane sapphire substrates grow preferentially with (100) and (111) orientations, respectively. The PLT films with a high La content have a low refractive index due to the decrease of the refractive index anisotropy. The propagation losses in PLT films measured, using He-Ne laser light and the prism coupling method decrease as the La content increases. This is due to the reduction of the refractive index anisotropy and the surface scattering by the surface roughness as a function of La content in the film.

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Synthesis and Electro-Optical Properties of Potassium Titanyl Phosphate thin Films by Sol-Gel Method

MRS Proceedings ◽

10.1557/proc-495-257 ◽

1997 ◽

Vol 495 ◽

Cited By ~ 1

Author(s):

Jianping Zhang ◽

Burtrand I. Lee ◽

Feiling Wang ◽

Melvin A. Leitheiser

Keyword(s):

Thin Films ◽

Refractive Index ◽

Optical Properties ◽

Sol Gel ◽

Structural Evolution ◽

Optical Devices ◽

Potassium Titanyl Phosphate ◽

Sol Gel Process ◽

Potential Applications ◽

Ft Ir

ABSTRACTPotassium titanyl phosphate, KTiOPO4 (KTP), thin films were prepared by sol-gel process. The structural evolution of KTP thin films was investigated by means of DTA/TGA, XRD, and FT-IR. The electro-optical results show that KTP thin films have a refractive index of 1.8 and large quadratic electro-optical coefficient of R=2.50643*10−16 and have potential applications for electro-optical devices.

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Anti-reflection and anti-static (AR/AS) coatings made by TiO2 sol-gel process with poly(3,4-ethylenedioxy thiophene)

e-Polymers ◽

10.1515/epoly.2008.8.1.89 ◽

2008 ◽

Vol 8 (1) ◽

Author(s):

Won Jung Kim ◽

Tae Young Kim ◽

Chin Su Park ◽

Jong Eun Kim ◽

Tae Hee Lee ◽

...

Keyword(s):

Refractive Index ◽

Sol Gel ◽

Nir Spectroscopy ◽

High Refractive Index ◽

Conducting Layer ◽

Uv Curable ◽

Sol Gel Process ◽

Refractive Index Layer ◽

Poly Ethylene ◽

Low Refractive Index

AbstractIn this study, we designed a two-layer hybrid Anti-Reflection/Anti-Static (AR/AS) thin film. Two kinds of UV-curable fluorinated compounds were synthesized as low refractive index materials, and a TiO2 sol combined with a conducting polymer, poly(3,4-ethylenedioxythiophene) was made by the sol-gel process for use as a high refractive index material as well as a conducting layer. In order to determine the most optimized AR/AS system, the spectral properties were simulated with the refractive index of each layer. According to the simulated results, a high refractive index layer was deposited on the hard coated poly(ethylene terephthalate) (PET) substrate by the spin coating technique, and a low refractive index layer was spin coated on the low refractive index layer. The reflectance and transmittance were measured by UV-VIS-NIR spectroscopy. It was found that the measured reflectance and the maximum transmittance of the AR/AS film were 0.71 %R at a wavelength of 550 nm and 93 %T in the wavelength range between 400 and 700 nm, respectively. The surface resistance of the AR/AS film was 108.6 ohms.

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The crystallization of thin-film ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122095 ◽

1992 ◽

Vol 50 (1) ◽

pp. 338-339

Author(s):

J.M. Schwartz ◽

L.F. Francis ◽

L.D. Schmidt ◽

P.S. Schabes-Retchkiman

Keyword(s):

Thin Films ◽

Grain Size ◽

Sol Gel ◽

Processing Route ◽

Small Areas ◽

Ceramic Thin Films ◽

Complex Shapes ◽

Sol Gel Process ◽

Ceramic Precursors ◽

Crystalline Ceramic

Ceramic thin films and coatings are of interest for electrical, optical, magnetic and thermal barrier applications. Critical for improved properties in thin films is the development of specific microstructures during processing. To this end, the sol-gel method is advantageous as a versatile processing route. The sol-gel process involves depositing a solution containing metalorganic or colloidal ceramic precursors onto a substrate and heating the deposited layer to form a crystalline or non-crystalline ceramic coating. This route has several advantages, including the ability to create tailored microstructures and properties, to coat large or small areas, simple or complex shapes, and to more easily prepare multicomponent ceramics. Sol-gel derived coatings are amorphous in the as-deposited state and develop their crystalline structure and microstructure during heat-treatment. We are particularly interested in studying the amorphous to crystalline transformation, because many key features of the microstructure such as grain size and grain size distribution may be linked to this transformation.

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Epitaxial Growth of Sr0.3Ba0.7Nb2O6 Thin Films Prepared by Sol-Gel Process

MRS Proceedings ◽

10.1557/proc-606-181 ◽

1999 ◽

Vol 606 ◽

Cited By ~ 2

Author(s):

Keishi Nishio ◽

Jirawat Thongrueng ◽

Yuichi Watanabe ◽

Toshio Tsuchiya

Keyword(s):

Thin Film ◽

Thin Films ◽

Epitaxial Growth ◽

Raw Materials ◽

Substrate Surface ◽

Sol Gel ◽

Tungsten Bronze ◽

Monomethyl Ether ◽

Tetragonal Tungsten Bronze ◽

Sol Gel Process

AbstructWe succeeded in the preparation of strontium-barium niobate (Sr0.3Ba0.7Nb2O6 : SBN30)that have a tetragonal tungsten bronze type structure thin films on SrTiO3 (100), STO, or La doped SrTiO3 (100), LSTO, single crystal substrates by a spin coating process. LSTO substrate can be used for electrode. A homogeneous coating solution was prepared with Sr and Ba acetates and Nb(OEt)5 as raw materials, and acetic acid and diethylene glycol monomethyl ether as solvents. The coating thin films were sintered at temperature from 700 to 1000°C for 10 min in air. It was confirmed that the thin films on STO substrate sintered above 700°C were in the epitaxial growth because the 16 diffraction spots were observed on the pole figure using (121) reflection. The <130> and <310> direction of the thin film on STO were oriented with the c-axis in parallel to the substrate surface. However, the diffraction spots of thin film on LSTO substrate sintered at 700°C were corresponds to the expected pattern for (110).

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Effect of Annealing temperature on the Structural and Magnetic Properties of TbxY3-xFe5O12(x = 0.0, 1.0, 2.0) Thin Films Prepared by Sol-Gel Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.501.236 ◽

2012 ◽

Vol 501 ◽

pp. 236-241 ◽

Cited By ~ 1

Author(s):

Ftema W. Aldbea ◽

Noor Bahyah Ibrahim ◽

Mustafa Hj. Abdullah ◽

Ramadan E. Shaiboub

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Room Temperature ◽

Annealing Temperature ◽

Sol Gel ◽

Vibrating Sample Magnetometer ◽

X Ray ◽

Garnet Phase ◽

Sol Gel Process ◽

Amorphous Structures

Thin films nanoparticles TbxY3-xFe5O12 (x=0.0, 1.0, 2.0) were prepared by the sol-gel process followed by annealing process at various annealing temperatures of 700° C, 800° C and 900° C in air for 2 h. The results obtained from X-ray diffractometer (XRD) show that the films annealed below 900°C exhibit peaks of garnet mixed with small amounts of YFeO3 and Fe2O3. Pure garnet phase has been detected in the films annealed at 900°C. Before annealing the films show amorphous structures. The particles sizes measurement using the field emission scanning electron microscope (FE-SEM) showed that the particles sizes increased as the annealing temperature increased. The magnetic properties were measured at room temperature using the vibrating sample magnetometer (VSM). The saturation magnetization (Ms) of the films also increased with the annealing temperature. However, different behavior of coercivity (Hc) has been observed as the annealing temperature was increased.

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