scholarly journals Optical and Structural Properties of CdS Quantum Dots Synthesized Using (MW-CBD) Technique

2020 ◽  
pp. 44-52
Author(s):  
Ahmed Ahmed S. Abed ◽  
Sattar J. Kasim ◽  
Abbas F. Abbas
Keyword(s):  
Thin Films ◽  
Quantum Dots ◽  
Room Temperature ◽  
Energy Gap ◽  
Cds Nanoparticles ◽  
Cds Quantum Dots ◽  
Optical Energy Gap ◽  
Glass Substrates ◽  
High Adhesion ◽  
Uv Visible

In the present study, the microwave heating method was used to prepare cadmium sulfide quantum dots CdSQDs films. CdS nanoparticles size average obtained as (7nm). The morphology, structure and composition of prepared CdSQDs were examined using (FE-SEM), (XRD) and (EDX). Optical properties of CdSQDs thin films formed and deposited onto glass substrates have been studied at room temperature using UV/ Visible spectrophotometer within the wavelength of (300-800nm), and Photoluminescence (PL) spectrum. The optical energy gap (Eg) which estimated using Tauc relation was equal (2.6eV). Prepared CdS nanoparticles thin films are free from cracks, pinholes and have high adhesion to substrate.

scholarly journals Optical and structural study for DLC thin films prepared by plasma jet

2019 ◽  
Vol 17 (40) ◽  
pp. 50-58
Author(s):  
S. J. Kadhem
Keyword(s):  
Thin Films ◽  
High Voltage ◽  
Plasma Torch ◽  
Energy Gap ◽  
Plasma Jet ◽  
Optical Energy Gap ◽  
X Ray ◽  
Xrd Diffraction ◽  
Fourier Transformation Infrared Spectroscopy ◽  
Uv Visible

Diamond-like carbon (DLC) homogeneous thin films were deposited from cyclohexane (Ccyclohexane (Ccyclohexane (Ccyclohexane (C cyclohexane (Ccyclohexane (Ccyclohexane (C cyclohexane (Ccyclohexane (C 6H12 ) liquid by using a plasma jet system which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5 which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5which operates with alternating high voltage 7.5 kv and kv and kv and kv and frequency 28 frequency 28frequency 28 frequency 28frequency 28frequency 28frequency 28frequency 28 kHz. kHz. The optical and structural properties and chemical bonding of these films were investigated. In this work, the effect of changing the distance between the substrate and the plasma torch (2, 2.5 and 3 cm) was studied. The flow rate of argon gas which used to generate the plasma was fixed (0.5 L/min). These films were characterized by UV–Visible spectrophotometer, X-ray diffractometer (XRD) and scanning electron microscopy (SEM) and Fourier transformation infrared spectroscopy (FTIR). The maximum absorption (λmax) appears around 312, 298.3 and 293.2 nm at the three distance between plasma torch and the substrate 2.5, 2 and 3 cm, respectively. The values of the optical energy gap are 3.47, 3.65 and 3.76 eV at a different distance (2, 2.5 and 3cm), respectively. In XRD diffraction pattern, The occurrence of diamond peaks and graphite peaks in the x-ray spectrum for these films Indicates that there is an occurrence of local ordered sp3 and sp2 for carbon domains and graphite respectively.

scholarly journals Effect of Pb percentage on optical parameters of PbxCd1-xSe thin films

2019 ◽  
Vol 14 (29) ◽  
pp. 1-7
Author(s):  
Farah Q. Kamil
Keyword(s):  
Thin Films ◽  
Thermal Evaporation ◽  
Energy Gap ◽  
Optical Measurements ◽  
Optical Parameters ◽  
Optical Energy Gap ◽  
Optical Energy ◽  
Glass Substrates

PbxCd1-xSe compound with different Pb percentage (i.e. X=0,0.025, 0.050, 0.075, and 0.1) were prepared successfully. Thin filmswere deposited by thermal evaporation on glass substrates at filmthickness (126) nm. The optical measurements indicated thatPbxCd1-xSe films have direct optical energy gap. The value of theenergy gap decreases with the increase of Pb content from 1.78 eV to1.49 eV.

Structural, Optical, and Optoelectrical Studies of Spray Pyrolyzed CuGaSnS4 Thin Films

2021 ◽  
Author(s):  
Islam M El radaf ◽  
Hnan Y Alzahrani
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Nonlinear Optical ◽  
Energy Gap ◽  
Structural Parameters ◽  
Stoichiometric Composition ◽  
Optical Energy Gap ◽  
Linear Absorption ◽  
Glass Substrates ◽  
D Values

Abstract We deposited CuGaSnS4 thin films on soda-lima glass substrates via a spray pyrolysis process. The X-ray diffraction of CuGaSnS4 films established the formation of an orthorhombic single phase. In addition, the structural parameters of the CuGaSnS4 films were estimated by Debye-Scherer’s formulas, which showed that an enhancement in crystallite size (D) values occurred by increasing the thickness of the investigated films. The EDAX pattern of CuGaSnS4 films confirms a stoichiometric composition. The optical results revealed that the CuGaSnS4 films possessed a direct optical energy gap (Eg). The Eg values were reduced from 1.50 to 1.38 eV with the increase in thickness. Also, there was an observed increase in the linear refractive index and the linear absorption coefficient values occurred due to the increased thickness. Finally, the optoelectrical constants of the sprayed CuGaSnS4 films such as the optical conductivity (σopt) and the optical free carrier concentration to effective mass (N_opt/m^* ) were enlarged with increasing film thickness. The nonlinear optical study showed that the increase in film thickness enhanced the nonlinear optical constants of CuGaSnS4 films. The hot-probe procedure shows that the sprayed CuGaSnS4 films expose p-type conductivity.

scholarly journals Structural and Optical Properties of (CdO)1-x(SnO2)x Thin Films Prepared by Pulsed Laser Deposition

2015 ◽  
Vol 59 ◽  
pp. 62-71
Author(s):  
Nahida B. Hasan ◽  
Ghusson H. Mohammed ◽  
Mohammed A. Abdul Majeed
Keyword(s):  
Thin Films ◽  
Pulsed Laser Deposition ◽  
Energy Gap ◽  
Optical Transition ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
X Ray Diffraction ◽  
Optical Energy Gap ◽  
Glass Substrates ◽  
Cdo Thin Films

CdO thin films have been deposited at different concentration of SnO2 (x= (0.0, 0.05, 0.1, 0.15 and 0.2)) Wt. % onto glass substrates by pulsed laser deposition technique (PLD) using Nd-YAG laser with λ=1064nm, energy=600mJ and number of shots=500. X-ray diffraction (XRD) results reveal that the deposited (CdO)1-x(SnO2)x thin films cubic structure and the grain size increase with increasing annealing temperature and increasing concentration of SnO2. The optical transition in the (CdO)1-x(SnO2)x thin films are observed to be allowed direct transition. The value of the optical energy gap decreases with increasing of annealing temperatures and increase with increasing concentration of SnO2 for all samples.

scholarly journals Impact of ZnO Atomic Ratio on Structural, Morphological and Some Optical Properties of (SnO2)1-x (ZnO)x Thin Films

2020 ◽  
pp. 333-340
Author(s):  
Donia Yas Khudair ◽  
Ramiz Ahmed Al Ansari
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Energy Gap ◽  
Atomic Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Glass Substrates ◽  
Atomic Force ◽  
Uv Visible ◽  
Longitudinal Structures

In this work, SnO2 and (SnO2)1-x(ZnO)x composite thin films with different ZnO atomic ratios (x=0, 5, 10, 15 and 20%) were prepared by pulsed laser deposition technique on clean glass substrates at room temperature without any treatment. The deposited thin films were characterized by x-ray diffraction atomic force microscope  and UV-visible spectrophotometer to study the effect of the ZnO atomic ratio on their structural, morphological and optical properties. It was found that the crystallinety and the crystalline size vary according to ZnO atomic ratio. The surface appeared as longitudinal structures which was convert to spherical shapes with increasing ZnO atomic ratio. The optical transmission and energy gap increased with increasing ZnO atomic ratio. 

InSe Nanothin Film with Ar-Gas Low Vacuum Pressure

2014 ◽  
Vol 606 ◽  
pp. 15-18
Author(s):  
Falah I. Mustafa ◽  
Mooroj Ali
Keyword(s):  
Thin Films ◽  
Diffraction Analysis ◽  
Room Temperature ◽  
Energy Gap ◽  
X Ray Diffraction ◽  
Argon Gas ◽  
X Ray ◽  
Glass Substrates ◽  
Deposited Film ◽  
Deposited Films

InxSe1-x(x = 0.4, 0.5, 0.6) thin films are deposited at room temperature on glass substrates with thickness ~500nm by thermal evaporation technique. The X-Ray diffraction analysis showed that both the as-deposited films In2Se3and InSe (x= 0.4 and 0.5) are amorphous in nature while the as-deposited film In3Se2is polycrystalline and the values of energy gap are Eg=1.44eV for In2Se3, Eg=1.16eV for InSe and Eg=0.78eV for In3Se2. The same technique used with insert Argon gas at pressure 0.1 mbar where InxSe1-x(x = 0.4, 0.5, 0.6) thin films are deposited at room temperature on glass substrates with thickness ~100nm. The X-Ray diffraction analysis showed that the as-deposited films In2Se3are amorphous in nature while the as-deposited film InSe and In3Se2are Nanocrystalline with grain size 33nm and 55nm respectively and the values of energy gap are Eg=1.55eV for InSe and Eg=1.28eV for In3Se2. The energy gap of InSe thin films increase with Argon gas assist and phases changes from amorphous and polycrystalline to nanostructure material by thermal vacuum deposition technique.

Thickness Dependence of Structural and Optical Characteristics of AZO Thin Films for Organic Photovoltaic Cells

2011 ◽  
Vol 117-119 ◽  
pp. 1076-1079
Author(s):  
S.L. Wei ◽  
L.H. Zeng ◽  
Z.Y. Zhong ◽  
J.H. Gu
Keyword(s):  
Thin Films ◽  
Energy Gap ◽  
Visible Spectrum ◽  
Rf Magnetron Sputtering ◽  
Optical Characteristics ◽  
Hexagonal Crystal ◽  
Optical Energy Gap ◽  
Glass Substrates ◽  
Aluminum Doped Zinc Oxide ◽  
Deposited Films

Aluminum-doped zinc oxide (AZO) thin films with highly (002)-preferred orientation were grown on glass substrates by rf magnetron sputtering. The effect of thickness on structural and optical characteristics of the deposited films were investigated by X-ray diffractometer and spectrophotometer. The results show that the polycrystalline AZO films consist of the hexagonal crystal structures with c-axis as the preferred growth orientation normal to the substrate, and that the thickness significantly affects the crystal structure and optical properties of the thin films. With the increase of thickness, the crystallite size of the films increases, the lattice spacing, dislocation density, micro strain and optical energy gap decrease, and the average transmitance in the wavelength range of the visible spectrum also slightly decreases.

scholarly journals Annealing effect on the optical properties of organic semiconductor Alq3: C60 blend thin films

2019 ◽  
Vol 16 (39) ◽  
pp. 1-10
Author(s):  
Lamiaa K. Abbas
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Annealing Temperature ◽  
Energy Gap ◽  
Bulk Heterojunction ◽  
Chemical Bonds ◽  
Optical Energy Gap ◽  
Heat Treated ◽  
Infra Red ◽  
Uv Visible

The effect of heat treatment using different annealing temperatures on optical properties of bulk heterojunction blend (BHJ) Alq3: C60 thin films which are fabricated by the spin coating technique were investigated in this study. The films have been coated on a glass substrate with speed of 2000 rpm for one min and treated with different annealing temperature (373, 423 and 473) K under vacuum. The optical properties and the chemical bonds structure of blends as-deposited and heat treated have been studied by UV-Vis spectroscopic and Fourier Transform-Infra Red (FTIR) measurements respectively. The results of UV visible show that the optical energy gap decreasing with increasing the annealing temperature for the ratio (100:1) while decreasing with increasing the annealing temperature for ratio (100:10). The FTIR spectra measurement were applied to know the type of the bonds of Alq3: C60 BHJ thin films.

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 influence of Deposition Temperature on the Properties of Chemically Sprayed Nanostructured Cu2CdSnS4 Thin Films

2020 ◽  
pp. 149-155
Author(s):  
Hiba J. Ahmed ◽  
Asaad A. Kamil ◽  
Ammar A. Habeeb ◽  
Nabeel A. Bakr
Keyword(s):  
Thin Films ◽  
Deposition Temperature ◽  
Energy Gap ◽  
Chemical Spray Pyrolysis ◽  
Optical Energy Gap ◽  
Spectra Analysis ◽  
Glass Substrates ◽  
Average Grain Size ◽  
Diffraction Patterns ◽  
P Type

In this study, Cu2CdSnS4 thin films were deposited on glass substrates at fixed concentrations: 0.02 M of (CuCl2.2H2O), 0.08 M of CS (NH2)2 and 0.01 M of both SnCl2.2H2O and (CdCl2.2H2O) using Chemical Spray Pyrolysis (CSP) technique at different deposition temperatures (300, 350, 400 and 450) °C. The thickness of all samples were (300 ± 10) nm. X-ray diffraction patterns showed that all films have a tetragonal structure with a preferred orientation of (112). The maximum value of the crystallite size was 8.09 nm at 400 °C deposition temperature. Raman spectra analysis confirmed the purity of the film peaks located at (332-333). The FESEM micrographs showed that the nanostructures appeared in the form of cauliflower. The highest average grain size was 62.8 nm for the film deposited at 300 °C substrate temperature. The optical properties of all films were studied by recording the transmittance and absorbance in the wavelength range (400-900) nm. The results showed that absorption occurs in the visible and ultraviolet regions. Through the Tauc’s equation, the optical energy gap was calculated for the allowed direct transition. Its value was in the range (1.59-1.40) eV. Therefore, these films are suitable for use in solar cell applications. Hall effect results showed that Cu2CdSnS4 thin films are p-type and the highest conductivity was 0.288 (Ω.cm)-1 at 400 ˚C corresponding to the maximum mobility value and the highest charge concentration.

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