scholarly journals Indium doped ZnO Urbach energy and dispersion parameters of thin films

2019 ◽  
Vol 12 (24) ◽  
pp. 75-80
Author(s):  
Saad Farhan Oboudi
Keyword(s):  
Thin Films ◽  
Energy Gap ◽  
Spray Pyrolysis Technique ◽  
Wide Band ◽  
Dispersion Parameters ◽  
Optical Energy Gap ◽  
Before And After ◽  
Single Oscillator ◽  
Absorption Measurements

The characterization of ZnO and ZnO:In thin films were confirmed by spray pyrolysis technique. The films were deposited onto glass substrate at a temperature of 450°C. Optical absorption measurements were also studied by UV-VIS technique in the wavelength range 300-900 nm which was used to calculate the optical constants. The changes in dispersion and Urbach parameters were investigated as a function of In content. The optical energy gap was decreased and the wide band tails were increased in width from 616 to 844 eV as the In content increased from 0wt.% to 3wt.%. The single–oscillator parameters were determined also the change in dispersion was investigated before and after doping.

scholarly journals Studying The Optical Properties of CdO and CdO: Bi Thin Films

2016 ◽  
Vol 13 (3) ◽  
pp. 593-598
Author(s):  
Baghdad Science Journal
Keyword(s):  
Thin Films ◽  
Energy Gap ◽  
Spray Pyrolysis Technique ◽  
Wave Length ◽  
Cadmium Oxide ◽  
Chemical Spray Pyrolysis ◽  
Optical Energy Gap ◽  
Chemical Spray ◽  
Before And After ◽  
20 Nm

Cadmium Oxide and Bi doped Cadmium Oxide thin films are prepared by using the chemical spray pyrolysis technique a glass substrate at a temperature of (400?C) with volumetric concentration (2,4)%. The thickness of all prepared films is about (400±20) nm. Transmittance and Absorbance spectra are recorded in the wave length ranged (400-800) nm. The nature of electronic transitions is determined, it is found out that these films have directly allowed transition with an optical energy gap of (2.37( eV for CdO and ) 2.59, 2.62) eV for (2% ,4%) Bi doped CdO respectively. The optical constants have been evaluated before and after doping.

scholarly journals Composition and Optical Dispersion Characterization of Nanoparticles ZnO-NiO Thin Films: Effect of Annealing Temperature

2013 ◽  
Vol 13 ◽  
pp. 78-86 ◽  
Author(s):  
Saad F. Oboudi ◽  
Nadir F. Habubi ◽  
Ghuson H. Mohamed ◽  
Sami S. Chiad
Keyword(s):  
Thin Films ◽  
Oscillator Strength ◽  
Annealing Temperature ◽  
Energy Gap ◽  
Dispersion Parameters ◽  
Optical Energy Gap ◽  
Optical Energy ◽  
Optical Dispersion ◽  
Glass Substrates ◽  
Before And After

Thin films of ZnO0.7NiO0.3 have deposited on glass substrates at room temperature by using thermal evaporation technique under vacuum 10-5 mbar. The optical properties and dispersion parameters of the films have been studied. Changes in direct optical energy band gap of films were confirmed before and after annealing. The optical energy gap Eg decreased from 3.11 to 2.86 eV with increasing of annealing temperature to 200 °C. Some of the optical absorption parameters, such as optical dispersion energies Eo and Ed, Urbach tails EU , dielectric constant ε, the average values of oscillator strength So, and wavelength of single oscillator λo have been reported. An increase in the annealing temperature causes an increase in the average oscillator strength from 62.02 to 87.71 eV.

scholarly journals Optical Dispersion Characterization of Sprayed Zn1-xMnxO Thin Films

2013 ◽  
Vol 9 ◽  
pp. 1-8
Author(s):  
Nadir F. Habubi ◽  
Sami Salmann Chiad ◽  
Saad Farhan Oboudi ◽  
Ziad Abdulahad Toma
Keyword(s):  
Doping Concentration ◽  
Energy Gap ◽  
Spray Pyrolysis Technique ◽  
Dispersion Parameters ◽  
Optical Energy Gap ◽  
Oscillator Parameter ◽  
Optical Energy ◽  
Glass Substrates ◽  
Single Oscillator ◽  
Urbach Tails

Uniform and adherent Zn1-xMnxO films have been deposited by using spray pyrolysis technique on glass substrates. The optical properties and dispersion parameters of zinc oxide have been studied as a function of doping concentration with Mn. Changes in direct optical energy band gap of cobalt oxide films were confirmed after doping, the optical energy gap Eg increased from 3.13 eV for the undoped ZnO to 3.39 eV with increasing the doping concentration of Mn to 4%. The changes in dispersion parameters and Urbach tails were investigated. An increase in the doping concentration causes a decrease in the average oscillator strength. The single-oscillator parameter has been reported.

scholarly journals A study of the characterization of CdS/PMMA nanocomposite thin film

2019 ◽  
Vol 14 (29) ◽  
pp. 191-197
Author(s):  
Awras H. Ajil
Keyword(s):  
Energy Gap ◽  
Spray Pyrolysis Method ◽  
Chemical Spray Pyrolysis ◽  
X Ray Diffraction ◽  
Optical Energy Gap ◽  
Host Matrix ◽  
Chemical Spray ◽  
Before And After ◽  
Co Precipitation

Nanocomposites of polymer material based on CdS as fillermaterial and poly methyl methacrylate (PMMA) as host matrix havebeen fabricated by chemical spray pyrolysis method on glasssubstrate. CdS particles synthesized by co-precipitation route usingcadimium chloride and thioacetamide as starting materials andammonium hydroxide as precipitating agent. The structure isexamined by X-ray diffraction (XRD), the resultant film hasamorphous structure. The optical energy gap is found to be (4.5,4.06) eV before and after CdS addition, respectively. Electricalactivation energy for CdS/PMMA has two regions with values of0.079 and 0.433 eV.

scholarly journals Molar Concentration Effects on the Optical and Structural Properties of Nanostructural SnO2 Thin Films

2016 ◽  
Vol 65 ◽  
pp. 80-90 ◽  
Author(s):  
Nadir F. Habubi ◽  
Ziad M. Abood ◽  
Ahmed N. Algamel
Keyword(s):  
Thin Films ◽  
Energy Gap ◽  
Spray Pyrolysis Technique ◽  
Quantum Confinement Effect ◽  
Film Surface ◽  
Molar Concentration ◽  
Chemical Spray Pyrolysis ◽  
Concentration Effects ◽  
Optical Energy Gap ◽  
Optical Energy

Thin films of nanostructured SnO2 with different molariteswere prepared by chemical spray pyrolysis technique. XRD analysis reveals that all the films were tetragonal polycrystalline with a preferred orientation along (110) plane. AFM measurements indicate that the value of the grain size for 0.05 M, 0.1 M and 0.15 M were 111nm, 78 nm and 58 nm respectively. SEM micrograph proved the existence of small cracks on the film surface, EDS confirmed the composition percentage ratio of Sn and O­2 and no trace of impurities could be detected. PL spectra gives the indication about optical energy gap and the effect of concentration on it which appeared as a blue shift. The transmittance was studied for the deposited thin films, identifying that the transmittance decreases by the increase in molarity. The value of the optical energy gap of the deposited thin films was increased upon increasing molar concentration due o quantum confinement effect. The Urbach energy was also studied, their values decrease as the molar concentration increase.

IMPACT OF N DOPING ON THE PHYSICAL PROPERTIES OF ZnO THIN FILMS

2018 ◽  
Vol 25 (01) ◽  
pp. 1850035 ◽  
Author(s):  
NRIPASREE NARAYANAN ◽  
N. K. DEEPAK
Keyword(s):  
Thin Films ◽  
Energy Gap ◽  
Spray Pyrolysis Technique ◽  
Compositional Analysis ◽  
Optical Transmittance ◽  
Xrd Analysis ◽  
Zno Thin Films ◽  
Optical Energy Gap ◽  
Glass Substrates ◽  
N Doping

Structural, optical and electrical properties of bare and N monodoped ZnO thin films were investigated. The samples were prepared on glass substrates by spray pyrolysis technique. N doping resulted in p type electrical conductivity as evident from the Hall measurement results. XRD analysis confirmed the structural purity of all the films and compositional analysis by energy dispersive X-ray spectroscopy verified the inclusion of N in doped films in addition to Zn and O. Doping resulted in deterioration in crystallinity. Optical transmittance got diminished with doping due to the degradation in crystallinity as well as due to the presence of deep N related defects as evident from the photoluminescence spectra. Optical energy gap red-shifted with doping percentage due to the introduction of impurity levels near the valence band edge within the forbidden gap with acceptor doping.

scholarly journals The Structural and Optical Properties of Cobalt dioxide (CoO2 )Thin Films deposited via (SCSP) Technique for photovoltaic applications

2021 ◽  
Vol 13 (01) ◽  
pp. 33-42
Author(s):  
Mushtaq Talib Al-Helaly ◽  
◽  
Nathera A .Al-Tememee ◽  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Energy Gap ◽  
Spray Pyrolysis Technique ◽  
Film Surface ◽  
Structural And Optical Properties ◽  
Optical Energy Gap ◽  
Optical Energy ◽  
X Ray ◽  
Photovoltaic Applications

The research included the preparation and then studying the structural and optical properties of the cobalt dioxide (CoO2)films. The latter films were prepared using a semi-computerized spray pyrolysis technique (SCSPT),. The X-ray diffraction gave polycrystalline nature with crystal system trigonal (hexagonal axes), and the Energy Dispersive X-ray spectroscopy (EDX) showed that all films contain the elements (Co and O) indicating formation of (CoO2) films with high purity. FTIR measurements showed of chemical bonds of CoO2 clearly. Scanning Electron Microscopy (SEM ) Showed clearly that the formed thin films under the optimum conditions were homogeneous, dense and compact, and Atomic Force Microscopy(AFM) results showed that the topography of the film surface where surface roughness was found to be 7.91 nm, root mean square was 9.69 nm., and the average granularity diameter was 78.00 nm. The optical properties (absorbance, absorption coefficient, extinction coefficient, refractive index, optical Conductivity, the real ε_(1 ) and imaginary ε_2 part of the dielectric constant )were decreased with increasing the wavelength, while the transmittance increases with increasing wavelength. The optical energy gap was (1.98eV) and this is a good optical energy gap values for photovoltaic applications.

scholarly journals Structural and Optical Properties of Fe2O3-NiO Mixed Thin Films Prepared by Chemical Spray Pyrolysis

2014 ◽  
Vol 33 ◽  
pp. 65-85 ◽  
Author(s):  
Noora J. Mohmmed ◽  
Nadir F. Habubi
Keyword(s):  
Thin Films ◽  
Spray Pyrolysis ◽  
Energy Gap ◽  
Spray Pyrolysis Technique ◽  
Chemical Spray Pyrolysis ◽  
Optical Energy Gap ◽  
Optical Energy ◽  
Afm Analysis ◽  
Chemical Spray ◽  
20 Nm

Mixed Fe2O3 - NiO thin films have been prepared by chemical Spray pyrolysis technique onto glass substrate preheated to 450 °C. The thickness of thin films was found to be (400 ±20) nm. XRD measurements reveal that all the film exhibit polycrystalline hexagonal wrutzite with a preferred orientation along (104) plane for pure and 10 % and 20 % Ni, while for the rest the structure was amorphous. AFM analysis indicate a nanostructure for all the films. The optical energy gap was found to be increased from optical transitions seems to be direct and the optical energy gap seems to be increased from 2.5 to 2.69 eV as the percentage of NiO increase.

scholarly journals Structural and optical properties of tungsten doped TiO2 thin films fabricated by spray pyrolysis technique

2020 ◽  
Vol 2 (1) ◽  
pp. 1-8
Author(s):  
Tamilnayagam V ◽  
Keerthika Kumarasamy ◽  
Tamiloli Devendhiran ◽  
Mohanraj K ◽  
Ilavarasan L
Keyword(s):  
Thin Films ◽  
Spray Pyrolysis ◽  
Energy Gap ◽  
Spray Pyrolysis Technique ◽  
Amorphous Structure ◽  
Tio2 Thin Films ◽  
Optical Energy Gap ◽  
Force Microscopy ◽  
Atomic Force ◽  
Double Beam

The pure and tungsten doped titanium oxide WxTi1-xO2 (x=0, 0.1) thin films have been successfully deposited on the glass substrate at 400 °C using spray pyrolysis technique. The structural properties of the prepared films were characterized by X-Ray Diffraction (XRD). From the XRD spectrum, the sample shows the amorphous structure. Their surface morphology was probed using Scanning Electron Microscopy (SEM) and the mechanical properties, topography and surface roughness of the grown films was investigated by Atomic Force Microscopy (AFM). The functional group and optical characteristic of prepared films were analyzed by Fourier Transform Infra-Red (FT-IR) spectroscopy and UV-Vis-double beam spectrometer.  The optical energy gap was determined by transmittance measurement.

INFLUENCE OF ANNEALING ON THE STRUCTURAL AND OPTICAL CHARACTERISTICS OF INDIUM OXIDE THIN FILMS PREPARED USING THERMAL EVAPORATION IN A VACUUM METHOD

2016 ◽  
pp. 4415-4421
Author(s):  
Saleem A. Hussain ◽  
Eman .A. Al-Hilo ◽  
Alyaa H Hatem
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Thermal Evaporation ◽  
Energy Gap ◽  
Optical Parameters ◽  
Optical Energy Gap ◽  
Calculated Energy ◽  
Average Grain Size ◽  
Before And After ◽  
Different Temperatures

In the work, the structures and the optical parameters were studied for In2O3 thin films Before and after annealing at different temperatures (400 and 500 ) thin films were prepared on glass substrate by by vacuum thermal evaporation. The X-Ray diffraction showed that In2O3, In2O3 Plasticizedthin films which were prepared to have a polycrystalline cubic structure. The most preferential orientation is along the (321) direction for all deposited In2O3 films. Some parameters of the films were calculated as the average grain size and the dislocation density. Optical properties measurement transmittance (T) of the film shows that they have high transmittance (82.7%) is obtained for at annealing 500 . The optical properties such as absorption coefficient (α) using the transmittance measurement from an UV-vis spectrophotometer, with a range of wavelength (300-1100) nm. And also calculated energy gap for thin films. and also calculated energy gap for thin films, the result has been shown that the optical energy gap increasing with increasing annealing.

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