Effect of Film thickness on the Photocatalytic Performance of Ti02 Thin Films Deposited by Spin Coating

Fabrication of surfactant-modified DNA thin films with high uniformity, specifically DNA–CTMA, has been well considered via drop-casting and spin-coating techniques. However, the fabrication of thin films with pure DNA has not been sufficiently studied. We characterize the uniformity of thin films from aqueous salmon DNA solutions mixed with ethanol, methanol, isopropanol, and acetone. Measurements of thickness and macroscopic uniformity are made via a focused-beam ellipsometer. We discuss important parameters for optimum uniformity and note what the effects of solvent modifications are. We find that methanol- and ethanol-added solutions provide optimal fabrication methods, which more consistently produce high degrees of uniformity with film thickness ranging from 20 to 200 nm adjusted by DNA concentration and the physical parameters of spin-coating methods.

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Fabrication by Spin-Coating and Optical Characterization of Poly(styrene-co-acrylonitrile) Thin Films

Coatings ◽

10.3390/coatings11091015 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1015

Author(s):

Elizabeth Hedl ◽

Ivana Fabijanić ◽

Iva Šrut Rakić ◽

Ivan Vadla ◽

Jordi Sancho-Parramon

Keyword(s):

Thin Films ◽

Refractive Index ◽

Film Thickness ◽

Spin Coating ◽

Visible Range ◽

Force Microscopy ◽

Atomic Force ◽

Linear Behavior ◽

Concentrated Solution ◽

Dependent Viscosity

The optical characteristics of poly(styrene-co-acrylonitrile) thin films obtained by spin-coating of polymer blend in tetrahydrofuran were investigated by spectroscopic ellipsometry, spectrophotometry, and atomic force microscopy. Film thickness can be broadly varied by changing the polymer concentration.The film thickness dependence on PSAN concentration shows a non-linear behavior that can be explained by a concentration-dependent viscosity. According to previously proposed models, prepared solutions are close to the concentrated solution regime. Films show a broad transparency range and refractive index independent of film thickness. The refractive index values range from 1.55 to 1.6 in the visible range. Thermal treatment revealed good stability of the films up to 220 °C and a progressive deterioration for larger temperatures, with evident damage at 300 °C. UV-induced photodegradation was observed and results showed a progressive decrease of transmittance in the range between 200 and 300 nm but PSAN thin films show no changes when exposed to light from a solar illuminator. These investigations indicate that PSAN is an excellent candidate for thin film polymer-based optical uses like interference coatings or encapsulation of solar cells.

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Thickness-dependent photocatalytic performance of nanocrystalline TiO2 thin films prepared by sol–gel spin coating

Applied Surface Science ◽

10.1016/j.apsusc.2013.05.053 ◽

2013 ◽

Vol 280 ◽

pp. 737-744 ◽

Cited By ~ 53

Author(s):

Chung-Yi Wu ◽

Yuan-Ling Lee ◽

Yu-Shiu Lo ◽

Chen-Jui Lin ◽

Chien-Hou Wu

Keyword(s):

Thin Films ◽

Spin Coating ◽

Photocatalytic Performance ◽

Sol Gel ◽

Tio2 Thin Films ◽

Nanocrystalline Tio2

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Correction to: Effect of film thickness on structural, morphological, and optical properties of Cu2ZnSnS4 thin films prepared by sol–gel spin coating

Applied Physics A ◽

10.1007/s00339-019-2791-6 ◽

2019 ◽

Vol 125 (8) ◽

Author(s):

T. Atwee ◽

A.-S. Gadallah ◽

M. A. Salim ◽

A. M. Ghander

Keyword(s):

Thin Films ◽

Optical Properties ◽

Film Thickness ◽

Spin Coating ◽

Sol Gel

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Influence of Film Thickness and Annealing Temperature on Optical Properties of Nanostructured-TiO2 Thin Films Prepared by Sol–Gel Spin Coating Technique

International Journal of Nanoscience ◽

10.1142/s0219581x16500289 ◽

2016 ◽

Vol 16 (02) ◽

pp. 1650028 ◽

Cited By ~ 1

Author(s):

A. A. A. Darwish ◽

F. S. Abu-Samaha ◽

Z. Mohamed ◽

M. M. El-Nahass

Keyword(s):

Thin Films ◽

Film Thickness ◽

Spin Coating ◽

Optical Constants ◽

Annealing Temperature ◽

Sol Gel ◽

Spin Coating Technique ◽

Tio2 Thin Films ◽

Coating Technique ◽

Quartz Substrates

TiO2 powder was found to be polycrystalline with rutile system. TiO2 films were deposited on quartz substrates by a sol–gel spin coating technique. X-ray diffraction and transmission electron microscope results have confirmed that the TiO2 films have nanostructure nature. It is found the crystallite size increased with annealing temperature. The optical constants of nanostructured TiO2 films were found to be independent of film thickness in the range from 100[Formula: see text]nm to 500[Formula: see text]nm. It is found that the optical constants and the dielectric constant of the thin films were all affected by annealing temperature. The existing allowed optical transitions in the as-deposited and annealed films were found to be direct and indirect transitions. Finally, the bandgaps of the as-deposited film were found to decrease with the annealing temperature.

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Modeling of Poly(methylmethacrylate) Viscous Thin Films by Spin-Coating

Coatings ◽

10.3390/coatings11020198 ◽

2021 ◽

Vol 11 (2) ◽

pp. 198

Author(s):

Navid Chapman ◽

Mingyu Chapman ◽

William B. Euler

Keyword(s):

Thin Films ◽

Film Thickness ◽

Spin Coating ◽

Design Space ◽

Three Dimensional ◽

Drying Rate ◽

Process Mapping ◽

Concentration Effects ◽

Coating Solution ◽

Toluene Concentration

A predictive film thickness model based on an accepted equation of state is applied to the spin-coating of sub-micron poly(methylmethacrylate) viscous thin films from toluene. Concentration effects on density and dynamic viscosity of the spin-coating solution are closely examined. The film thickness model is calibrated with a system-specific film drying rate and was observed to scale with the square root of spin speed. Process mapping is used to generate a three-dimensional design space for the control of film thickness.

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Giant Anisotropy of Conductivity in Hydrogenated Nanocrystalline Silicon Thin Films

MRS Proceedings ◽

10.1557/proc-536-275 ◽

1998 ◽

Vol 536 ◽

Author(s):

A. B. Pevtsov ◽

N. A. Feoktistov ◽

V. G. Golubev

Keyword(s):

Thin Films ◽

Film Thickness ◽

Percolation Theory ◽

Nanocrystalline Silicon ◽

Spatial Light Modulators ◽

Light Emitting ◽

Light Modulators ◽

Silicon Thin Films ◽

Longitudinal Conductivity ◽

Transverse Conductivity

AbstractThin (<1000 Å) hydrogenated nanocrystalline silicon films are widely used in solar cells, light emitting diodes, and spatial light modulators. In this work the conductivity of doped and undoped amorphous-nanocrystalline silicon thin films is studied as a function of film thickness: a giant anisotropy of conductivity is established. The longitudinal conductivity decreases dramatically (by a factor of 109 − 1010) as the layer thickness is reduced from 1500 Å to 200 Å, while the transverse conductivity remains close to that of a doped a- Si:H. The data obtained are interpreted in terms of the percolation theory.

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STRUCTURAL, OPTICAL PROPERTIES AND PHOTOCATALYTIC ACTIVITY OF NANOCRYSTALLINE TiO2 THIN FILMS DEPOSITED BY SOL-GEL SPIN COATING

i-manager s Journal on Material Science ◽

10.26634/jms.7.1.15719 ◽

2019 ◽

Vol 7 (1) ◽

pp. 28

Author(s):

KOMARAIAH DURGAM ◽

RADHA EPPA ◽

REDDY M. V. RAMANA ◽

KUMAR J. SIVA ◽

R. SAYANNA ◽

...

Keyword(s):

Thin Films ◽

Optical Properties ◽

Photocatalytic Activity ◽

Spin Coating ◽

Sol Gel ◽

Tio2 Thin Films ◽

Nanocrystalline Tio2

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Sol-gel growth of Ni doped CdS on glass substrates: effect of spin coating speed and dopant concentration

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681210999200423120817 ◽

2020 ◽

Vol 10 ◽

Author(s):

Atefeh Nazari Setayesh ◽

Hassan Sedghi

Keyword(s):

Thin Films ◽

Optical Properties ◽

Spin Coating ◽

Optical Band Gap ◽

Dopant Concentration ◽

Rotation Speed ◽

Sol Gel ◽

Band Gap Energy ◽

Gap Energy ◽

Glass Substrates

Background: In this work, CdS thin films were synthesized by sol-gel method (spin coating technique) on glass substrates to investigate the optical behavior of the film. Methods: Different substrate spin coating speeds of 2400, 3000, 3600 rpm and different Ni dopant concentrations of 0 wt.%, 2.5 wt.%, 5 wt.%) were investigated. The optical properties of thin films such as refraction index, extinction coefficient, dielectric constant and optical band gap energy of the layers were discussed using spectroscopic ellipsometry method in the wavelength range of 300 to 900 nm. Results: It can be deduced that substrate rotation speed and dopant concentration has influenced the optical properties of thin films. By decreasing rotation speed of the substrate which results in films with more thicknesses, more optical interferences were appeared in the results. Conclusion: The samples doped with Ni comparing to pure ones have had more optical band gap energy.

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