scholarly journals The Effect of Substrate Temperature on the Band Transition, Cauchy Dispersion and Urbach Energy of Nanostructure CdO Thin Films

2015 ◽  
Vol 58 ◽  
pp. 83-89
Author(s):  
Muneer H. Jadduaa ◽  
Zainab Ali Harbi ◽  
Nadir F. Habubi
Keyword(s):  
Thin Films ◽  
Substrate Temperature ◽  
Urbach Energy ◽  
Energy Gap ◽  
Chemical Spray Pyrolysis ◽  
Optical Parameters ◽  
Optical Energy Gap ◽  
Substrate Temperature Increase ◽  
Band Transition ◽  
Cdo Thin Films

Thin films of CdO were prepared by chemical spray pyrolysis (CSP) . The effect of different temperature substrate (300,350,400,450 and 500) °C on some optical parameters has been studied . The transmittance and the optical energy gap were increased from (2.503-2.589) eV ,on the contrary of the rest parameters such as refractive index , real and imaginary parts of dielectric constant and Urbach energy which they were decreased as the substrate temperature increase.

scholarly journals Study Influence of Substrate Temperature on Optical Properties of CdS Thin Films Prepared by Chemical Spray pyrolysis

2019 ◽  
Vol 32 (1) ◽  
pp. 6 ◽  
Author(s):  
Karrar Mahdi Saleh
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Substrate Temperature ◽  
Spray Pyrolysis ◽  
Energy Gap ◽  
Nitrate Solution ◽  
Chemical Spray Pyrolysis ◽  
Optical Energy Gap ◽  
Chemical Spray ◽  
Cds Thin Films

This study aims to prepare Cadmium Sulphide (CdS) thin films using thermal Chemical Spray Pyrolysis (CSP) on glass of different temperatures substrate from cadmium nitrate solution. Constant thickness was (430 ± 20 nm) and the effect of substrate temperature on the optical properties of prepared thin films. Optical properties have been studied from transmittance and absorbance spectral within wavelengths range (360 - 900 nm). The results show that all the prepared films have a direct electron transitions and optical energy gap between (2.31-2.44 eV). They also show that the transmittance and optical energy gap of films prepared from nitrate solution increase with increasing of substrate temperature, then transmittance start downward with the continued increase in temperature (400, 450) oC.

scholarly journals Effect of Substrate Temperature on Structural and Optical Properties of CdO Thin Films

2014 ◽  
Vol 27 ◽  
pp. 47-55
Author(s):  
Hanan R.A. Ali
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Optical Properties ◽  
Substrate Temperature ◽  
Energy Gap ◽  
Spray Pyrolysis Technique ◽  
Xrd Analysis ◽  
Structural And Optical Properties ◽  
Optical Energy Gap ◽  
Cdo Thin Films

Thin films of CdO have been prepared by spray pyrolysis technique. XRD analysis reveals that all the prepared samples were polycrystalline and have preferred orientation along [111] orientation. The surface topography was determined by AFM which indicate that surface roughness and rms roughness were increased by the increasing of substrate temperature. The optical energy gap were determined and its value lies between (2.4-2.5) eV.

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.

EFFECT OF SUBSTRATE TEMPERATURE ON THE STRUCTURAL AND OPTICAL PROPERTIES OF NiTsPc THIN FILMS

2019 ◽  
Vol 27 (03) ◽  
pp. 1950124 ◽  
Author(s):  
MOHAMMED YARUB HANI ◽  
ADDNAN H. AL-AARAJIY ◽  
AHMED M. ABDUL-LETTIF
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Optical Properties ◽  
Substrate Temperature ◽  
Energy Gap ◽  
Chemical Spray Pyrolysis ◽  
Structural And Optical Properties ◽  
Absorption Bands ◽  
Tauc Plot ◽  
Substrate Temperatures

Nickel(II) phthalocyanine-tetrasulfonic acid tetrasodium salt (NiTsPc) thin films were deposited on glass substrates at different substrate temperatures ([Formula: see text]) by chemical spray pyrolysis (CSP) technique. The substrate temperature varied from 110∘C to 310∘C in 50∘C steps. The substrate surface temperature is the main parameter that determines the film morphology and properties of the thin films. The structural properties of the deposited NiTsPc thin films were investigated by X-ray diffraction (XRD) and from the obtained results, it was shown that depositing thin films using 210∘C as [Formula: see text] results in higher crystallinity. Atomic force microscope (AFM) was employed to obtain the surface topography and to calculate the roughness and grain size. The smoothest thin film surface was obtained when using at 160∘C, while the highest roughness was obtained at 310∘C. The optical properties were investigated by ultraviolet visible (UV-Vis) spectrophotometer and fluorescence spectrophotometer. From the absorption spectra recorded in the wavelength range 190–1100[Formula: see text]nm, two absorption bands were observed, which are known as Soret and Q-band. By observing the absorption spectrum, it can be concluded that the deposited thin films at 110∘C–310∘C have direct energy gap. From Tauc plot relation, the energy gap ([Formula: see text]) was calculated. The values of the energy gap were between 3.05 and 3.14[Formula: see text]eV. It was observed that different [Formula: see text] highly affects the structural and optical properties of the deposited thin films. The crystallinity, grain size, roughness and the optical properties were strongly affected by the different substrate temperatures.

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.

scholarly journals Annealing Effects on the Interband Transition and Optical Constants of Cobalt Doped Cadmium Oxide Thin Films

2015 ◽  
Vol 43 ◽  
pp. 81-90 ◽  
Author(s):  
Nadir F. Habubi
Keyword(s):  
Thin Films ◽  
Optical Constants ◽  
Annealing Temperature ◽  
Energy Gap ◽  
Interband Transition ◽  
Cadmium Oxide ◽  
Spray Pyrolysis Method ◽  
Optical Parameters ◽  
Annealing Effects ◽  
Cdo Thin Films

The CdO: Co films have been deposited on substrate temperature at 400 °C by spray pyrolysis method using cadmium chloride and cobalt chloride as a precursors for Cd and Co ions, respectively. The effect of annealing temperature on optical constants of Co: CdO thin films are investigated using UV-Visible spectrophotometer in the range of (300-900) nm at room temperature. The absorbance and optical parameters such as α, n, ε1, ε2, and χ are increased when the annealing temperature increases, while the energy gap decreased from 2.5 eV before annealing to 2.48 eV after 500 °C annealing temperature. Urbach energy is increased with the increasing of annealing temperature from 353 meV for sample before annealing to 715 meV for the same samples annealed at 500 °C.

scholarly journals Hydrogenated Nano-Crystalline Silicon Thin Films in SiO2 Matrix for Next Generation Solar Cells Using Glow Discharged Decomposition

2018 ◽  
Vol 8 (1) ◽  
pp. 25
Author(s):  
Moniruzzaman Syed ◽  
Cameron Hynes ◽  
Brittany Anderson ◽  
Temer S Ahmadi ◽  
Boon Tong Goh ◽  
...  
Keyword(s):  
Thin Films ◽  
Substrate Temperature ◽  
Energy Gap ◽  
Volume Fraction ◽  
Crystalline Silicon ◽  
Strong Dependence ◽  
Blue Shift ◽  
Nanocrystalline Silicon ◽  
Optical Energy Gap ◽  
Substrate Temperatures

Hydrogenated Nanocrystalline Silicon (nc-Si:H) thin films using SiH4/H2 mixture by glow discharged decomposition were investigated on c-Si and glass substrates. The effects of substrate temperature on the Structural, Optical and Electrical properties of the films were investigated by X-ray diffraction, Raman scattering, FT/IR, Optical transmission and Atomic Force Microscopy (AFM). Substrate temperatures ([TSB]) of the films were changed from 100oC to 250oC. It has been revealed the strong dependence on the film’s properties with the substrate temperatures. XRD and Raman measurements were shown that the higher substrate temperature (250oC) exhibits the highest crystalline volume fraction ([ρ] = 95%) and the lowest crystalline size ([Ω] = 3.5 nm) as well, having the highest H-content and the lowest O-content. At 250oC, the lowest mobility and the highest resistivity were also found to be ~37.5 cm2/v.s and 7.35 Ω-cm. Refractive index and the optical energy gap (Eg) were estimated by 3.8 and 1.9 eV having the growth rate of 4.2 nm/min. At 250oC, it was resulted in a blue shift of the absorption edge having uniform grain distributions. Results indicate that in situ hydrogen cleaning effects is prominent and localized orderly high density Si-Si bonds are exhibiting quantum size effects at highest substrate temperature.

Tailoring Structural Properties of Polyethylene Terephthalate (PET) by 200 keV Ar+ Implantation

2013 ◽  
Vol 665 ◽  
pp. 221-226 ◽  
Author(s):  
Mahak Chawla ◽  
Rubi Rubi ◽  
Rajiv Kumar ◽  
Annu Sharma ◽  
Sanjeev Aggarwal ◽  
...  
Keyword(s):  
Polyethylene Terephthalate ◽  
Structural Changes ◽  
Urbach Energy ◽  
Energy Gap ◽  
Optical Parameters ◽  
Spectroscopic Techniques ◽  
Structural Behaviour ◽  
Optical Energy Gap ◽  
Uv Visible ◽  
Fluence Range

In the present work, our aim is to reveal the effect of Ar+implantation on the structural behaviour of Polyethylene terephthalate (PET) using Fourier Transform Infrared and UV-Visible Spectroscopic techniques. PET specimens were implanted with 200 keV Ar+ions in the fluence range of 1x1015to 1x1017ions cm-2. The structural changes have been observed due to change in the position and intensity of the bands in the FTIR spectra of both implanted and unimplanted specimens. A continuous decrease in optical energy gap (from 3.63 eV to 1.48 eV) and enhancement in Urbach energy (from 0.29 eV to 3.70 eV) with increasing ion dose have been observed. The structural changes have been correlated with the optical parameters observed in PET specimens as a result of implantation.

scholarly journals Preparation and Characterization of In2O3-CuO Nanocomposite Thin Films as NH3 Gas Sensor

2021 ◽  
pp. 2204-2212
Author(s):  
Abd alhameed A. Hameed ◽  
Hamid S. AL-Jumaili
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Copper Oxide ◽  
Gas Sensor ◽  
Indium Oxide ◽  
Energy Gap ◽  
Nanocomposite Films ◽  
Spray Pyrolysis Method ◽  
Chemical Spray Pyrolysis ◽  
Optical Energy Gap

      An NH3 gas sensor was prepared from nanocomposite films of indium oxide-copper oxide mixtures with ratios of 0 , 10 , and 20 Vol % of copper oxide. The films were deposited on a glass substrate using chemical spray pyrolysis method (CSP) at 400oC. The structural properties were studied by using X-ray diffraction (XRD) and atomic force microscopy ( AFM). The structural results showed that the prepared thin films are polycrystalline, with nano grain size. By mixing copper oxide with indium oxide, the grain size of the prepared thin films was decreased and the surface roughness was increased. The UV-Visible spectrometer analysis showed that the prepared thin films have high transmittance. This transmittance was decreased by mixing copper oxide with indium oxide. The direct optical energy gap ranged 3.5 - 3 eV, which was decreased with increasing copper oxide concentration. The sensitivity of the prepared gas sensor was measured towards NH3 gas at a concentration of 71ppm with operating temperatures of 100, 150, 200, 250 and 30) oC, according to the change of sensor resistance. This sensitivity of the mixture oxides showed a value of about nine times greater than that of individual indium oxide thin films. The results of the optimum gas sensor properties demonstrated a sensitivity value of 75.06%, response time of 10s, and recovery time of 11 s, at a mixing ratio of 20% of copper oxide and an operating temperature of 200oC.

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.

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