EFFECT OF DEPOSITION TEMPERATURE ON THE PROPERTIES OF TIO2 THIN FILMS DEPOSITED BY MOCVD

2016 ◽  
Vol 23 (02) ◽  
pp. 1650001 ◽  
Author(s):  
ZAKI S. KHALIFA
Keyword(s):  
Crystal Structure ◽  
Thin Films ◽  
Dielectric Constant ◽  
Refractive Index ◽  
Optical Properties ◽  
Deposition Temperature ◽  
Energy Gap ◽  
Organic Chemical ◽  
Tio2 Thin Films ◽  
Optical Energy Gap

Crystal structure, microstructure, and optical properties of TiO2 thin films deposited on quartz substrates by metal-organic chemical vapor deposition (MOCVD) in the temperature range from 250[Formula: see text]C to 450[Formula: see text]C have been studied. The crystal structure, thickness, microstructure, and optical properties have been carried out using X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), atomic force microscope (AFM), and UV-visible transmittance spectroscopy, respectively. XRD patterns show that the obtained films are pure anatase. Simultaneously, the crystal size calculated using XRD peaks, and the grain size measured by AFM decrease with the increase in deposition temperature. Moreover, the texture of the films change and roughness decrease with the increase in deposition temperature. The spectrophotometric transmittance spectra have been used to calculate the refractive index, extinction coefficient, dielectric constant, optical energy gap, and porosity of the deposited films. While the refractive index and dielectric constant decrease with the increase of deposition temperature, the porosity shows the opposite.

scholarly journals Constructing Spray Pyrolysis System for the Preparation of Thin Films and Study the Optical Properties of PbO Films

2015 ◽  
Vol 53 ◽  
pp. 146-153
Author(s):  
Nahida B. Hasan ◽  
Mohammed Ahmed Mohammed
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Spray Pyrolysis ◽  
Lead Oxide ◽  
Energy Gap ◽  
Absorbance Spectrum ◽  
Optical Energy Gap ◽  
Direct Energy ◽  
Direct Energy Gap

In this paper, the design of spray pyrolysis system to prepare thin films of various materials system. The study showed that films prepared with good characteristics. films were prepared from lead oxide PbO this way. The study of the optical properties of these films and through recording the absorbance spectrum and transmittance spectrum of films prepared in the wavelength range (300-1100) nm . Optical constant for thin films prepared such as absorption coefficient, the extinction coefficient , the refractive index and the optical energy gap was calculated as well. films prepared found that it has a direct energy gap value 3.1eV.

scholarly journals Study the effect of fish on the optical properties of CuO membranes prepared in a way that thermal spraying chemical

2006 ◽  
Vol 3 (1) ◽  
pp. 56-61
Author(s):  
Baghdad Science Journal
Keyword(s):  
Dielectric Constant ◽  
Refractive Index ◽  
Optical Properties ◽  
Research Study ◽  
Energy Gap ◽  
Thermal Spraying ◽  
Optical Energy Gap ◽  
Optical Energy ◽  
Calculated Energy ◽  
Optical Films

In this research study the effect of fish on the properties optical films thickness 1200-1800 and calculated energy gap Basra direct transport permitted and forbidden to membranes and urged decreasing values ??of Optical Energy Gap increase fish included accounts optical also calculate the constants visual as factories winding down and the refractive index and reflectivity membranes also by real part and imaginarythe dielectric constant

scholarly journals Influence of annealing temperature on the structural and optical properties of As30Te70 thin films

2017 ◽  
Vol 35 (2) ◽  
pp. 335-345 ◽  
Author(s):  
A.M. Abd-Elnaiem ◽  
M. Mohamed ◽  
R.M. Hassan ◽  
A.A. Abu-Sehly ◽  
M.A. Abdel-Rahim ◽  
...  
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Glass Transition ◽  
Extinction Coefficient ◽  
Chalcogenide Glasses ◽  
Annealing Temperature ◽  
Energy Gap ◽  
Optical Parameters ◽  
Optical Energy Gap

Abstract Chalcogenide glasses have attracted much attention largely due to their interesting physical and chemical properties. Though few published articles exist on the As-Te system, little is known about the optical properties of eutectic or near eutectic composition of As-Te system upon heat treatment. Therefore, this paper reports the effects of annealing temperature on the structural and optical parameters of As30Te70 thin films. The bulk and thin films of 150 nm thick As30Te70 chalcogenide glasses were prepared by melt-quenching and thermal evaporation techniques, respectively. The glass transition and crystallization reactions of the bulk samples were investigated using differential scanning calorimetry (DSC). The influence of annealing temperature on the transformation of the crystal structure was studied by X-ray diffraction (XRD), while the surface morphology of the annealed samples was examined using scanning electron microscope (SEM). The optical band gap, refractive index and extinction coefficient were also calculated. The DSC scans showed that the melting temperature remains constant at 636.56 K. In addition, other characteristic temperatures such as the glass transition temperature, the onset crystallization temperature, and the crystallization peak temperature increase with increasing the heating rate. The crystalline phases for the as-prepared and annealed films consist of orthorhombic As, hexagonal Te, and monoclinic As2Te3 phases. Furthermore, the average crystallite size, strain, and dislocation density depend on the annealing temperature. The optical absorption results revealed that the investigated films have a direct transition, and their optical energy gap decreases from 1.82 eV to 1.49 eV as the annealing temperature increases up to 433 K. However, the refractive index, extinction coefficient, dielectric constant and the ratio of free carrier concentration to its effective mass, increase with increasing the annealing temperature.

scholarly journals The effect of heat treatment on the optical properties of organic semiconductor (NiPc/C60) thin films

2019 ◽  
Vol 16 (39) ◽  
pp. 33-41
Author(s):  
Atheer M. Mkhaiber
Keyword(s):  
Crystal Structure ◽  
Thin Films ◽  
Optical Properties ◽  
Optical Absorption ◽  
Annealing Temperature ◽  
Energy Gap ◽  
Optical Absorption Spectra ◽  
Optical Energy Gap ◽  
Optical Energy ◽  
Glass Substrates

Thin films of the blended solution of (NiPc/C60) on glass substrates were prepared by spin-coated method for three different ratios (100/1, 100/10 and 100/100). The effects of annealing temperature and C60 concentration on the optical properties of the samples were studied using the UV-Vis absorption spectroscopy and FTIR spectra. The optical absorption spectrum consists of two main bands, Q and B band, with maxima at about (602-632) nm and (700-730) nm for Q1 and Q2 respectively, and (340-375) nm for B band. The optical energy gap were determined from optical absorption spectra, The variation of optical energy gap with annealing temperature was nonsystematic and this may be due to the improvement in crystal structure for thin films. While the energy gap decreased by increasing the concentration of C60 approaches from the energy gap of this compound.

scholarly journals Enhancement of the solubility of polyaniline and studying the optical properties of (PANI+PVA) polymers blends.

2019 ◽  
Vol 13 (27) ◽  
pp. 83-90
Author(s):  
Nadia M. Hassan
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Refractive Index ◽  
Acidic Medium ◽  
Optical Transmission ◽  
Energy Gap ◽  
Optical Energy Gap ◽  
Linear Behavior ◽  
Optical Dielectric Constant ◽  
Optical Dielectric

The optical transmission and UV-VIS absorption spectra have been recorded in the wavelength range (200-1100m) for different composition of polyaniline and polyvinyl Alcohol(PVA ) blends thin films. Polyaniline was prepared in acidic medium to enhancement the solubility and processibility, The optical energy gap (Eopt) refractive index and optical dielectric constant real and imaginary part have been evaluated. The effects of doping percentage of prepared polyaniline on these parameters was discussed and the non –linear behavior for all these parameters was investigated.

scholarly journals Preparation and Studying the Optical Properties of (Sb2o3) Thin Films

2018 ◽  
Vol 26 (10) ◽  
pp. 249-256
Author(s):  
Waleed Khalid Kadhim
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Refractive Index ◽  
Optical Properties ◽  
Absorption Coefficient ◽  
Thermal Evaporation ◽  
Glass Slide ◽  
Antimony Trioxide ◽  
Hot Plate ◽  
Different Thickness

In this paper I present the preparation of (Sb2o3) thin films using thermal evaporation in vacuum, procedure with different thickness  (100 ,150 ,200 ,and 250) nm, by using ( hot plate) from Molybdenum matter at temperature in ( 9000c) and the period of time (15mint) ,the prepared in a manner thermal evaporation in a vacuum and precipitated on glass bases, pure Antimony Trioxide (sb2o3 ) thin films with various condition have been successfully deposited by (T.E.V) on glass slide substrates. The substrates temperature of about 100oC and the vacuum of about 10-6 torr, to investigated oxidation of evaporated, measure spectra for prepared films in arrange of wavelength (250 – 1100 nm). The following optical properties have been calculated: the absorption coefficient, the forbidden (Eg) for direct and indirect transitions "absorbance, refractive index,  extinction coefficient, real and imaginary parts" of the dielectric constant.

scholarly journals Annealing Effect on Some Optical Properties of Cr2O3 Thin Films Prepared by Spray Pyrolysis Technique

2011 ◽  
Vol 8 (2) ◽  
pp. 561-565
Author(s):  
Baghdad Science Journal
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Refractive Index ◽  
Optical Properties ◽  
Absorption Coefficient ◽  
Spray Pyrolysis ◽  
Annealing Temperature ◽  
Spray Pyrolysis Technique ◽  
Annealing Effect ◽  
Before And After

Cr2O3 thin films have been prepared by spray pyrolysis on a glass substrate. Absorbance and transmittance spectra were recorded in the wavelength range (300-900) nm before and after annealing. The effects of annealing temperature on absorption coefficient, refractive index, extinction coefficient, real and imaginary parts of dielectric constant and optical conductivity were expected. It was found that all these parameters increase as the annealing temperature increased to 550°C.

Investigation of Optical Properties of Aluminium Doped Zinc Oxide Thin Films Deposited by Magnetron Sputtering

2013 ◽  
Vol 446-447 ◽  
pp. 259-262
Author(s):  
J.H. Gu ◽  
T. Zhang ◽  
Z.Y. Zhong ◽  
C.Y. Yang ◽  
J. Hou
Keyword(s):  
Thin Films ◽  
Zinc Oxide ◽  
Refractive Index ◽  
Magnetron Sputtering ◽  
Structural Properties ◽  
Energy Gap ◽  
Dispersion Model ◽  
Argon Pressure ◽  
Optical Energy Gap ◽  
Characterization Methods

Aluminium doped zinc oxide (AZO) thin films were prepared by magnetron-sputtering. The optical and structural properties of the films were investigated by optical transmission spectra and X-ray diffraction (XRD) measurements, respectively. The results indicate that the AZO films have hexagonal wurtzite structure with highly c-axis preferred orientation. The optical and structural properties of the films are observed to be subjected to the argon pressure. The AZO film prepared at the argon pressure of 0.5 Pa exhibits the largest crystallite size and the highest average visible transmittance. Also, the refractive index and optical energy-gap of the films were determined by optical characterization methods. The dispersion behavior of the refractive index was studied using the Sellmeier’s dispersion model.

scholarly journals Studies on Surface Morphology and Electrical Conductivity of PS Thin Films in Presence of Divalent Complexes

2019 ◽  
Vol 16 (3) ◽  
pp. 0588 ◽  
Author(s):  
Al-Taa'y Et al.
Keyword(s):  
Thin Films ◽  
Electrical Conductivity ◽  
Refractive Index ◽  
Surface Morphology ◽  
Structural Modification ◽  
Energy Gap ◽  
Three Dimensional ◽  
Optical Parameters ◽  
Optical Energy Gap ◽  
Energy Gaps

       Optical properties and surface morphology of pure and doped Polystyrene films with different divalent metals of Zn, Cu and Sn and one concentration percentage have been studied. Measurements of UV-Vis spectrophotometer and AFM spectroscopy were determined. The absorbance, transmittance and reflectance spectrums were used to study different optical parameters such as absorption coefficient, refractive index, extinction coefficient and energy gap in the wavelengths rang 200-800nm. These parameters have increased in the presence of the metals. The change in the calculated values of energy gaps with doping metals content has been investigated in terms of PS matrix structural modification. The value of optical energy gap was found decreasing from 4.5eV of pure PS to reach 4.45, 4.38 and 4.32eV for Zn, Cu and Sn respectively. Measurement by AFM spectroscopy was done for two and three dimensional topographic images. From figures, the data of roughness average were 7.29, 7.31, 3.37 and 6.73nm for samples (Blank, Zn, Cu and Sn) respectively.

Preparation and Study the Electrical and Optical Properties for (PVA-PEG-Sr2O3) Nanocomposites

2021 ◽  
Vol 19 (10) ◽  
pp. 47-55
Author(s):  
Safa Ahmed Jabbar Al-Rubaye ◽  
Nassar A. Al-lsawi ◽  
Ali R. Abdulridha
Keyword(s):  
Dielectric Constant ◽  
Refractive Index ◽  
Optical Properties ◽  
Electrical Properties ◽  
Dielectric Loss ◽  
Energy Gap ◽  
Antimony Oxide ◽  
Optical And Electrical Properties ◽  
Electrical And Optical Properties ◽  
Constant E

In the presented work, the optical and electrical properties of composite materials (PVA-PEG-Sr2O3) were measured, as the electrical properties were verified at various frequencies in range of 100 Hz-6 MHz. In addition, the experimental results showed that the increase in frequency causes a reduction in the dielectric loss (δ) and dielectric constant (ɛ), and there is an increase in ɛ due to the increase in the content of antimony oxide (Sr2O3). It increases with increasing frequency and decreases with increasing Sr2O3 content in PVA-PEG-Sr2O3 compounds, the result of the optical properties of the nanoparticles (PVA-PEG-Sr2O3) showed that the values transmittance and energy gap were reduced with the increases in the concentrations of Sr2O3 NPs, whereas the values related to extinction coefficient, absorption coefficient, optical conductivity, refractive index, and dielectric constant (imaginary, real) were increased with increase in the concentration of Sr2O3 NPs.

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