scholarly journals Optical properties of alumina films by sol gel acrylamide route

2021 ◽  
Vol 23 (10) ◽  
pp. 38-43
Author(s):  
G. Ramanathan ◽  
◽  
K.R. Murali ◽  
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Annealing Temperature ◽  
Optical Band Gap ◽  
Sol Gel ◽  
Gelling Agent ◽  
Absorption Bands ◽  
Ammonium Persulphate ◽  
Alumina Films ◽  
Different Temperatures

A new acrylamide route was applied to prepare alumina films by using aluminum chloride as a starting material and ammonium persulphate solution as the gelling agent. The XRD results show that the films are amorphous for the post anneals temperatures up to 300 °C, beyond this temperature; peaks corresponding to γ-Al2O3 are observed. XPS studies indicated the peaks corresponding to the Al 2p spectra of films after annealing at different temperatures. The FTIR spectra reveal absorption bands of Al-O and to lattice. The absorption co-efficient was 1014 cm- 1.Refractive index was in the range of 1.71 to 1.61 with increase of wavelength from 250-500 nm. Optical band gap value was around 5.40-5.75 eV with increase of annealing temperature.

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.

scholarly journals Effect of Annealing Temperature on the Structural and Optical Properties of TiO2 Thin Film Prepared by Sol-gel Method

2016 ◽  
Vol 8 (3) ◽  
pp. 267-272 ◽  
Author(s):  
F. U. Khan ◽  
M. Zubair ◽  
M. Z. Ansar ◽  
M. K. Alamgir ◽  
S. Nadeem
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Surface Morphology ◽  
Annealing Temperature ◽  
Sol Gel ◽  
Rutile Phase ◽  
Structural And Optical Properties ◽  
Tio2 Thin Films ◽  
Different Temperatures ◽  
Xrd Patterns

The effect of annealing temperatures on the surface morphology and optical properties of titanium dioxide (TiO2) thin films deposited by spin coating on Silicon substrate was studied. The TiO2 thin films deposited onto silicon substrates were annealed at different temperatures. The structural and optical properties were studied using scanning electron microscopy (SEM), X-ray diffraction technique (XRD) and optical ellipsometer. The results indicated that the structural properties of the TiO2 thin films were changed with the increase in annealing temperature. The SEM investigation showed that as annealing temperature was increased, the grain and pores size were increased. The XRD patterns of the studied samples showed that rutile phase were found in a sample annealed at high temperature. The ellipsometry investigation shows that the refractive index increased while energy band gap decreased with the annealing temperature. The results showed that surface porosity, optical properties and surface morphology of TiO2 could be affected by changing the annealing temperature.   

scholarly journals Effect of Postdeposition Annealing on the Structural, Electrical, and Optical Properties of DC Magnetron SputteredTa2O5Films

2007 ◽  
Vol 2007 ◽  
pp. 1-5 ◽  
Author(s):  
S. V. Jagadeesh Chandra ◽  
P. Sreedhara Reddy ◽  
G. Mohan Rao ◽  
S. Uthanna
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Annealing Temperature ◽  
Optical Band Gap ◽  
Optical Transmittance ◽  
Electrical Characteristics ◽  
Electrical And Optical Properties ◽  
Tantalum Target ◽  
Deposited Films

Thin films of tantalum oxide were formed on quartz and silicon (111) substrates kept at room temperature (303 K) by reactive sputtering of tantalum target in the presence of mixture of oxygen and argon gases. The as-deposited films were annealed in air for an hour in the temperature range 673–873 K. The films were characterized by studying structural, dielectric, electrical, and optical properties. The as-deposited films were amorphous in nature. As the annealing temperature increased to 673 K, the films were transformed into polycrystalline. Electrical characteristics of as-deposited and annealedTa2O5thin films were compared. The thermal annealing reduced the leakage current density and increased the dielectric constant. The optical transmittance of the films increased with the increase of annealing temperature. The as-deposited films showed the optical band gap of 4.38 eV. It increased to 4.44 eV with the increase of annealing temperature to 873 K. The as-deposited films showed the low value (1.89) of refractive index and it increased to 2.15 when annealed at 873 K. The increase of refractive index with annealing temperature was due to the increase in the packing density and crystallinity of the films.

scholarly journals Structural and optical properties of SrTiO3 nano material obtained by sol-gel method

2017 ◽  
Vol 27 (2) ◽  
pp. 173
Author(s):  
Doan Thi Thuy Phuong ◽  
Nguyen Xuan Huy ◽  
Le Thi Mai Oanh ◽  
Do Danh Bich ◽  
Trieu Thi Minh Chau
Keyword(s):  
Optical Properties ◽  
Annealing Temperature ◽  
Optical Band Gap ◽  
Sol Gel ◽  
Nano Particles ◽  
Structural And Optical Properties ◽  
Raman Analysis ◽  
Sol Gel Process ◽  
Nano Material ◽  
Quality Material

SrTiO3 nano particles were prepared by sol-gel process in order to optimize the temperature condition to obtain good quality material for different applications. The thermal treating condition was selected out through XRD, FTIR and Raman analysis of the synthesized power. The structural and optical property of the powder were studied carefully with XRD, SEM, FTIR, Raman and UV-Vis measurement. At optimized annealing temperature (from 900 oC to 1000 oC), the synthesized STO nano particles have good structure. The shape, size and optical band gap of obtained material are suitable for further applications.

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.

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.

Study the Effect of Heat Treatment and Pressure on some the Optical Properties of the Pure PVA Nano Polymer

2021 ◽  
Vol 900 ◽  
pp. 16-25
Author(s):  
Tabarak Mohammed Awad ◽  
May A.S. Mohammed
Keyword(s):  
Heat Treatment ◽  
Dielectric Constant ◽  
Refractive Index ◽  
Optical Properties ◽  
Absorption Coefficient ◽  
Polyvinyl Alcohol ◽  
Complex Dielectric Constant ◽  
Different Temperatures ◽  
German Origin ◽  
Increasing Temperature

In this study, some optical properties were studied of the pure vinyl polyvinyl alcohol (PVA) nanopolymer (German origin). Under the influence of different temperatures and pressures of PVA. Where 25 samples were prepared for the purpose of conducting the research. Which studied the study of these samples was done by recording the absorbance and transmittance spectra of the wavelengths (200-900) nm. From them, absorbance, transmittance, reflectivity, absorption coefficient, refractive index, extinction coefficient, complex dielectric constant were calculated. At different temperatures (25,40, 80, 120, 160)°C. And with different pressures within the range (7.5,8,8.5,9,9.5) MPa. The results are that the permeability of the polymer (PVA) at different temperatures for each pressure decreases with increasing temperature, and that all other calculated optical properties increase with increasing temperature.

Effect of annealing temperature on the structural and optical properties of ZnO thin films prepared by sol–gel method

Ionics ◽  
2010 ◽  
Vol 16 (9) ◽  
pp. 815-820 ◽  
Author(s):  
Yidong Zhang ◽  
Wenjun Fa ◽  
Fengling Yang ◽  
Zhi Zheng ◽  
Pingyu Zhang
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Annealing Temperature ◽  
Sol Gel ◽  
Zno Thin Films ◽  
Structural And Optical Properties ◽  
Gel Method ◽  
Sol Gel Method
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