Structure and Optical Properties of Nanocrystalline Yttria Doped Ceria Thin Films

1998 ◽  
Vol 12 (15) ◽  
pp. 1573-1583 ◽  
Author(s):  
A. Hartridge ◽  
M. Ghanashyam Krishna ◽  
A. K. Bhattacharya
Keyword(s):  
Thin Films ◽  
Optical Band Gap ◽  
Dopant Concentration ◽  
Sol Gel ◽  
Doped Ceria ◽  
Optical Losses ◽  
Glass Substrates ◽  
A Value ◽  
Free Region ◽  
Yttria Doped Ceria

Thin films of Ce 1-x Y x O 2-y where x ranges from 0 to 0.5 have been coated onto glass substrates using an inorganic sol–gel approach at low temperature. The lattice parameters from powder diffraction measurements were calculated and shown to be very close to those previously reported. Crystallite size measurements indicated that the films were nanocrystalline, the size decreasing as a function of dopant concentration. The films are transparent in the region 500 to 1500 nm with very low optical losses. The film refractive index is dependent on the dopant concentration and peaks at an yttria concentration of x=0.25 after treatment at 450° C , with a value of 1.79, which on increasing the yttria concentration to x=0.50 decreases to 1.65 in the dispersion free region. The optical band gap is also dependent on the dopant concentration and is in the range 3.2 to 3.0 eV.

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

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.

OPTICAL PROPERTIES OF NANOCRYSTALLINE YTTERBIA DOPEDC ZIRCONIA THIN FILMS

2000 ◽  
Vol 14 (09) ◽  
pp. 1017-1024
Author(s):  
A. HARTRIDGE ◽  
M. GHANASHYAM KRISHNA ◽  
A. K. BHATTACHARYA
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Annealing Temperature ◽  
Optical Band Gap ◽  
Dopant Concentration ◽  
Sol Gel ◽  
Fluorite Structure ◽  
Optical Losses ◽  
Cubic Structure ◽  
Quartz Substrates

Thin films of Zr 1-x Yb x O 2-y where x ranges from 0 to 0.3 have been coated onto quartz substrates using an inorganic sol–gel approach at low temperature. The films were fully crystalline and continuous as deposited, with a fluorite structure. On heating over 900°C, films with less than 16% doping had a tetragonal structure whilst those above retained a cubic structure. Crystallite size measurements indicated that the films were nanocrystalline, the size decreasing as a function of increasing dopant concentration. The films are transparent in the region 500 to 1500 nm with very low optical losses. The film refractive index seems relatively independent of the dopant concentration. The optical band gap is dependent on the dopant concentration and is in the range 5.6 to 5.7 eV. There is an increase in refractive index and decrease in optical absorption with increase in annealing temperature from 600°C to 1050°C.

Properties of TiO2 Thin Film Prepared by Sol-Gel Dip Coating

2015 ◽  
Vol 723 ◽  
pp. 528-531
Author(s):  
Jun Wang ◽  
Ling Yun Bai
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Band Gap ◽  
Optical Band Gap ◽  
Sol Gel ◽  
Dip Coating ◽  
Gel Method ◽  
Glass Substrates

TiO2 thin films were prepared on glass substrates by sol-gel method. The effect of withdraw speed on the thickness and optical properties of TiO2 thin films was investigated. The films were transparent in the visible wavelength. The thickness of the TiO2 films was increased from 90 nm for the withdraw speed of 1000 μm/s to 160 nm for the withdraw speed of 2000 μm/s. While, The refractive index of the TiO2 thin film decreased from 2.38 to 2.07. It may be due to the porosity of the film was increased. The optical band-gap of the films was around 3.45 eV.

Fabrication and characterization of Yb-doped Y2O3 powders and thin films

2020 ◽  
Vol 111 (7) ◽  
pp. 559-566
Author(s):  
Elif Emil Kaya ◽  
Fatma Ünal ◽  
Kürşat Kazmanlıa ◽  
Sebahattin Gürmena
Keyword(s):  
Thin Films ◽  
Crystallite Size ◽  
Dopant Concentration ◽  
Sol Gel ◽  
Lattice Parameter ◽  
Electron Beam Evaporation ◽  
Glass Substrates ◽  
Corning Glass ◽  
Peak Broadening ◽  
Evaporation Technique

Abstract Yttrium oxide (Y2O3) and ytterbium (Yb)-doped Y2O3 particles were synthesized via the sol-gel method from the aqueous solution of their nitrate salts. The synthesized powders were then deposited on Corning glass substrates using an electron beam evaporation technique to examine the growth morphology of the thin films. The effect of the Yb dopant concentration on the microstructure and morphology of the Y2O3 powders and thin films was investigated using various characterization techniques. The synthesized powders and fabricated thin films have body-centered cubic structures with space group Ia-3. Based on the X-ray peak broadening, crystallite size and lattice parameters were evaluated with the Williamsom-Hall and Cohen-Wagner methods. The lattice parameter and crystallite size decrease with increasing Yb concentration. The intensities of the Raman peaks decrease due to microstructural disorder caused by the increase in the Yb dopant concentration. The band gap values of the powders also decrease depending on the dopant concentration, similar to the lattice parameter and crystallite size. While the synthesized powders have a sponge-like morphology, they exhibit different morphological structures depending on the dopant concentration when converted into thin films.

ANNEALING TREATMENT OF ZnO THIN FILMS DEPOSITED BY SOL–GEL METHOD

2012 ◽  
Vol 19 (05) ◽  
pp. 1250055 ◽  
Author(s):  
M. SALEEM ◽  
L. FANG ◽  
Q. L. HUANG ◽  
D. C. LI ◽  
F. WU ◽  
...  
Keyword(s):  
Thin Films ◽  
Spin Coating ◽  
Annealing Temperature ◽  
Optical Band Gap ◽  
Sol Gel ◽  
Annealing Treatment ◽  
Zno Thin Films ◽  
Axis Orientation ◽  
Transmittance Spectra ◽  
Glass Substrates

Highly transparent ZnO thin films were deposited on glass substrates by using a simple and inexpensive multi-step sol–gel spin coating process. This research investigated the effects of annealing temperature in the range from 350–600°C on the microstructure, surface morphology and optical properties of thin films by using XRD, SEM and transmittance spectra. The XRD results showed that the c-axis orientation of ZnO thin films was improved with the increase of annealing temperature. The grain size increases from 16.6–19.7 nm with the increase in temperature. The transmittance spectra indicated that the transmittance and direct optical band gap Eg of the films showed a decreased trend with annealing temperature. It is found that the tensile stress exist in the films, which decreases with the increase in annealing temperature up to 500°C, on further increasing the annealing temperature up to 600°C, the stress in the film changes from tensile to compressive nature.

STRUCTURE AND OPTICAL PROPERTIES OF NANOCRYSTALLINE ERBIA DOPED ZIRCONIA THIN FILMS

2000 ◽  
Vol 14 (11) ◽  
pp. 1239-1248 ◽  
Author(s):  
A. HARTRIDGE ◽  
M. GHANASHYAM KRISHNA ◽  
A. K. BHATTACHARYA
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Dopant Concentration ◽  
Sol Gel ◽  
Fluorite Structure ◽  
X Ray Diffraction ◽  
A Value ◽  
Crystallite Sizes ◽  
Quartz Substrates ◽  
Similar Peak

Thin films of zirconia doped with erbia in the concentration range of 5 to 15% have been prepared on quartz substrates by an inorganic and aqueous sol–gel method. The films were crystalline, continuous and single phase as deposited, with a cubic fluorite structure and crystallite sizes of 8–10 nm as shown by X-ray diffraction. The films were annealed to 600 and 1050°C after deposition and found to be transparent in the region between 400 to 1100 nm, the crystalline structure becoming tetragonal at 1050°C with crystallite sizes of around 30–40 nm. The refractive index increased with increase in annealing temperature. There is a peak in the refractive index at a dopant concentration of 10% where it achieves a value of 1.88 at 700 nm. The optical absorption edge shows a similar peak at the same dopant concentration with a value of 5.65 eV.

scholarly journals Correlation of film thickness to optical band gap of Sol-gel derived Ba0.9Gd0.1TiO3 thin films for optoelectronic applications

2017 ◽  
Vol 162 ◽  
pp. 01042
Author(s):  
Yen Chin Teh ◽  
Ala’eddin A. Saif ◽  
Zul Azhar Zahid Jamal ◽  
Prabakaran Poopalan
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Band Gap ◽  
Optical Band Gap ◽  
Sol Gel ◽  
Optoelectronic Applications

Microstructural, Optical and Electrical Properties of ZnO:Sn Thin Films Deposited by Sol-Gel Method

2013 ◽  
Vol 652-654 ◽  
pp. 519-522
Author(s):  
Jun Chen ◽  
Yue Hui Hu ◽  
Hong Hao Hu ◽  
Yi Chuan Chen
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Sol Gel ◽  
Hexagonal Structure ◽  
Optical And Electrical Properties ◽  
Axis Orientation ◽  
Gel Method ◽  
Sol Gel Method ◽  
Sn Doping ◽  
Glass Substrates

Transparent thin films of Sn-doped ZnO (ZnO:Sn) were deposited onto silica glass substrates by the sol–gel method. The effect of different Sn doping on the crystallinity, structural, optical and electrical properties of ZnO:Sn thin films were investigated by XRD, SEM, UV-VIS spectrophotometer and four-point probe method respectively. Among all of ZnO:Sn thin films in this paper, Sn-doped with 2 at.% exhibited the best properties, the surface demonstrate an accumulative crystallization and hexagonal structure, with a high-preferential c-axis orientation, namely an average transmittance of 90% and the resistivity of 19.6 Ω·cm.

Preparation and characterization of V2O5 doped SiO2-TiO2 thin films

2012 ◽  
Vol 2 (1) ◽  
Author(s):  
Marek Nocuń ◽  
Sławomir Kwaśny
Keyword(s):  
Thin Films ◽  
Band Gap ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Dip Coating ◽  
Band Gap Energy ◽  
Tio2 Thin Films ◽  
Glass Substrates ◽  
Gel Technique

AbstractIn our investigation, V doped SiO2/TiO2 thin films were prepared on glass substrates by dip coating sol-gel technique. Chemical composition of the samples was studied by X-ray photoelectron spectroscopy (XPS). Transmittance of the samples was characterized using UV-VIS spectrophotometry. Subsequently band-gap energy (Eg) was estimated for these films. Powders obtained from sols were characterized by FTIR spectroscopy. It was found that vanadium decreases optical band gap of SSiO2/TiO2 films.

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