scholarly journals Study of Composition and Optical Properties of Chemically Deposited Pd-xSb2S3 Thin Films

2017 ◽  
Vol 7 (3) ◽  
Author(s):  
Patrick Akata Nwofe
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Band Gap ◽  
Energy Band ◽  
Bath Temperature ◽  
Morphological Properties ◽  
Optical Absorption Coefficient ◽  
Complexing Agents ◽  
Energy Band Gap ◽  
Rutherford Back Scattering

The study reports on the effects of different concentration of palladium impurities on the compositional and optical properties of Palladium Doped Antimony Sulphide (Pd-xSb2S3) thin films grown by the chemical bath deposition method. The films were grown at room temperature and other deposition conditions such as the bath temperature, pH, complexing agents were kept constant. The concentration of the dopants were varied between 0.1 M to 0.3 M. The films were annealed at an annealing temperature of 200  oC  for 1 hour. The films were characterised using the Rutherford Back Scattering (RBS) techniques and optical spectroscopy (transmittance versus wavelength, absorbance versus wavelength) to investigate the composition, and optical constants (optical absorption coefficient, energy band gap, and extinction coefficient) respectively. X-ray diffractometry and Scanning electron microscopy were also used to investigate the structural and morphological properties of the layers. The results show that the transmittances of the doped layers were higher compared to the as-deposited layers. The energy band gap was direct, and were found to be decreased for the doped layers, compared to the as-grown films. The values of the energy band gap were typically ≤ 2.30 eV for the former and 2.48 eV for the latter. These values strongly suggest the use of these films in optoelectronic applications especially in solar cell devices.

scholarly journals Characterization of silver polyaniline nanocomposite thin films prepared by microwave induced plasma

2019 ◽  
Vol 13 (28) ◽  
pp. 1-9
Author(s):  
Ahmad S. Wassfi
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Band Gap ◽  
Ag Nanoparticles ◽  
Energy Band ◽  
Average Particle ◽  
Energy Band Gap ◽  
Optical Energy ◽  
Microwave Induced Plasma ◽  
Nanocomposite Thin Films

Polyaniline (PANI) and Ag/PANI nanocomposite thin films have prepared by microwave induced plasma. The Ag powder of average particle size of 50 nm, were used to prepare Ag/PANI nanocomposite thin films. The Ag/PANI nanocomposite thin films prepared by polymerization in plasma and characterized by UV-VIS, FTIR, AFM and SEM to study the effect of silver nanoparticles on the optical properties, morphology and structure of the thin films. The optical properties studies showed that the energy band gap of the Ag/PANI (5%wt silver) decreased from 3.6 to 3.2 eV, where the substrate location varied from 4.4 to 3.4 cm from the axis of the cylindrical plasma chamber. Also the optical energy gap decreased systematically from 3.3 to 3 eV with increasing Ag nanoparticles, where Ag concentration increased from 5% to 11%wt. The FTIR measurement showed a shifting in the FTIR absorption peaks with Ag concentration. AFM and SEM images indicate that there are a few clusters of Ag and there is a uniform distribution of the Ag nanoparticles in the PANI matrix. It can be concluded that Ag/PANI nanocomposite thin films with controlled optical energy band gap can be prepared by microwave induced plasma technique.

scholarly journals Structural and optical properties of Co and Ni doped ZnO thin films prepared by RF magnetron sputtering

2017 ◽  
Vol 18 (3) ◽  
pp. 302-308 ◽  
Author(s):  
I.D. Stolyarchuk ◽  
G.I. Kleto ◽  
A. Dziedzic
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Optical Absorption ◽  
Surface Morphology ◽  
Band Gap ◽  
Energy Band ◽  
Zno Thin Films ◽  
Optical Absorption Spectra ◽  
Energy Band Gap ◽  
Structural And Optical Properties

We have reported the effect of Co and Ni doping on structural and optical properties of ZnO thin films prepared by RF reactive sputtering technique. The composite targets were formed by mixing and pressing of ZnO, Mn3O4, CoO and NiO powders. The thin films were deposited on sapphire, quartz and glass substrates. The structure study confirms the formation of the hexagonal wurtzite ZnO without any secondary phase in transition metal (Co, Ni) - doped samples. Cross-sectional TEM images of all studied samples show a denseand uniformly textured structure composed of column-like structure along the growth direction. The surface morphology of the thin films was studied using atomic force microscopy (AFM). Different surface morphology (AFM) images were obtained depending on the film composition and growth conditions. Optical absorption spectra suggest of substitution Zn2+ ions in ZnO lattice by transition metal atoms. The shift of the absorption edge due to decrease the energy band gap with increasing cobalt content and complex dependence of the energy band gap on content of nickel was observed in optical absorption spectra of the studied films. The room temperature photoluminescence peaks are attributed to near band gap emission and vacancy or defect states.

scholarly journals Effect of Dopant Concentration on the Structural, Optical and Sensing Properties of (SnO2)1-x(TiO2:CuO)x Sprayed Films

2019 ◽  
Vol 16 (2) ◽  
pp. 0361
Author(s):  
Mahmood Et al.
Keyword(s):  
Optical Properties ◽  
Band Gap ◽  
Energy Band ◽  
Spray Pyrolysis Technique ◽  
Single Crystal Silicon ◽  
Dielectric Constants ◽  
Energy Band Gap ◽  
Crystal Silicon ◽  
X Ray ◽  
Regular Manner

      Spray pyrolysis technique was subjected to synthesized (SnO2)1-x (TiO2: CuO) x Thin films on different substrates like glass and single crystal silicon using. The structure of the deposited films was studied using x-ray diffraction. A more pronounced diffraction peaks of SnO2 while no peaks of (CuO , TiO2 ) phase appear in the X-ray profiles by increasing of the content of (TiO2 , CuO) in the sprayed films. Mixing concentration (TiO2 , CuO) influences on the size of the crystallites of the SnO2 films ,the size of crystallites of the spray paralyzed oxide films change in regular manner by increasing of (TiO2 , CuO) amount. The effect of mixing concentration on the optical properties of the films was also investigated. The reflectance and transmittance spectra  in the wavelength range (300-1100) nm were employed to determine the optical properties such as energy band gap (Eg) and refractive index (n),  extinction coefficient  (k) , real and imaginary parts of dielectric constants (ε1, ε2) for (SnO2)1-x(TiO2:CuO)x films. The energy band gap omit of which showed reduction from (3.65 to 2.2) eV by reducing of SnO2 amount from (100 to 70) % .The reduction of energy band gap was ascribed to the new tail states introduced in the band gap of tin oxide. The sensitivity of the prepared sensor film was determined resistance difference of the films when exposed to oxidizing gas. The data declared that the mixed SnO2 films have better sensitivity in comparison with unmixed films.

scholarly journals Optoelectronics applications of electrodeposited p- and n-type Al2Se3 thin films

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
A. A. Faremi ◽  
S. S. Oluyamo ◽  
O. Olubosede ◽  
I. O. Olusola ◽  
M. A. Adekoya ◽  
...  
Keyword(s):  
Thin Films ◽  
Electrical Conductivity ◽  
Band Gap ◽  
Energy Band ◽  
Selenium Dioxide ◽  
Photoelectrochemical Cells ◽  
Energy Band Gap ◽  
Cathodic Deposition ◽  
Conductivity Type ◽  
P Type

Abstract In this paper, energy band gaps and electrical conductivity based on aluminum selenide (Al2Se3) thin films are synthesized electrochemically using cathodic deposition technique, with graphite and carbon as cathode and anode, respectively. Synthesis is done at 353 K from an aqueous solution of analytical grade selenium dioxide (SeO2), and aluminum chloride (AlCl2·7H2O). Junctions-based Al2Se3 thin films from a controlled medium of pH 2.0 are deposited on fluorine-doped tin oxide (FTO) substrate using potential voltages varying from 1,000 mV to 1,400 mV and 3 minutes −15 minutes respectively. The films were characterized for optical properties and electrical conductivity using UV-vis and photoelectrochemical cells (PEC) spectroscopy. The PEC reveals a transition in the conduction of the films from p-type to n-type as the potential voltage varies. The energy band gap reduces from 3.2 eV to 2.9 eV with an increase in voltage and 3.3 eV to 2.7 eV with increase in time. These variations indicate successful fabrication of junction-based Al2Se3 thin films with noticeable transition in the conductivity type and energy band gap of the materials. Consequently, the fabricated Al2Se3 can find useful applications in optoelectronic devices.

Optical Properties of Thin Films of Haycockite

MRS Advances ◽  
2019 ◽  
Vol 4 (37) ◽  
pp. 2023-2033
Author(s):  
Barys Korzun ◽  
Marin Rusu ◽  
Thomas Dittrich ◽  
Anatoly Galyas ◽  
Andrey Gavrilenko
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Chemical Composition ◽  
Energy Band ◽  
Surface Photovoltage ◽  
Second Phase ◽  
Energy Band Gap ◽  
Flash Evaporation ◽  
Glass Substrates ◽  
Evaporation Technique

ABSTRACTThin films of haycockite Cu4Fe5S8 on glass substrates were deposited by flash evaporation technique from powders of this compound. The composition of thin films correspond to the atomic content of Cu, Fe, and S of 24.13, 27.90, and 47.97 at.% with the Cu/ Fe and S/ (Cu + Fe) atomic ratios of 0.87 and 0.92 respectively, whereas the corresponding theoretical values for this material amount to 0.80 and 0.89. The as-prepared thin films of haycockite consist of a set of separate fractions of approximately identical areas of about 400 - 600 μm2. It can be assumed that this structure evolved during cooling down of thin films since it completely covers the surface of thin films. A small inclusion of a second phase with the chemical composition close to talnakhite Cu9Fe8S16 is also observed. Haycockite Cu4Fe5S8 is found to be a direct gap semiconductor with the energy band gap Eg equal to 1.26 eV as determined using both transmission and surface photovoltage methods.

Energy Band Gap Shift of ZnS-ZnO Thin Films Grown by Pulsed Laser Deposition

2010 ◽  
Vol 404 (1) ◽  
pp. 186-191 ◽  
Author(s):  
J.-K. Chung ◽  
J. W. Kim ◽  
D. Do ◽  
S. S. Kim ◽  
T. K. Song ◽  
...  
Keyword(s):  
Thin Films ◽  
Pulsed Laser Deposition ◽  
Band Gap ◽  
Energy Band ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Zno Thin Films ◽  
Energy Band Gap

Properties of CdS Thin Films Grown by Chemical Bath Deposition as a Function of Bath Temperature

2009 ◽  
Vol 609 ◽  
pp. 243-247 ◽  
Author(s):  
H. Moualkia ◽  
S. Hariech ◽  
M.S. Aida
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Band Gap ◽  
Chemical Bath Deposition ◽  
Bath Temperature ◽  
Band Gap Energy ◽  
X Ray Diffraction ◽  
Glass Substrates ◽  
Cds Thin Films ◽  
Direct Band

The present work deals with the preparation and characterization of cadmium sulfur (CdS) thin films. These films are prepared by chemical bath deposition on the well cleaned glass substrates. The thickness of the samples was measured by using profilometer DEKTAK, structural and optical properties were studied by X-ray diffraction analysis, and UV-visible spectrophotometry. The optical properties of the films have been investigated as a function of temperature. The band gap energy and Urbach energy were also investigated as a function of temperature. From the transmittance data analysis the direct band gap ranges from 2.21 eV to 2.34 eV. A dependence of band gap on temperature has been observed and the possible raisons are discussed. Transmission spectra indicates a high transmission coefficient (75 %). Structural analysis revealed that the films showed cubic structure, and the crystallite size decreased at a higher deposition temperature.

scholarly journals Dependence on the Partial Pressure of Oxygen on the Shift in the Energy Band-gap of CdO Thin Films in the Visible Region

2001 ◽  
Vol 24 (1) ◽  
pp. 57-61 ◽  
Author(s):  
M. A. Grado-Caffaro ◽  
M. Grado-Caffaro ◽  
S. L. Sapienza
Keyword(s):  
Thin Films ◽  
Partial Pressure ◽  
Band Gap ◽  
Energy Band ◽  
Visible Region ◽  
Point Of View ◽  
Theoretical Point ◽  
Partial Pressure Of Oxygen ◽  
Energy Band Gap ◽  
Cdo Thin Films

In this paper, the dependence on the partial pressure of oxygen of the shift in the energy band-gap of CdO thin films for the visible region is investigated from the theoretical point of view on an experimental basis. In our analysis, the role played by the dependence of the carrier density upon the above pressure is emphasized.

Sign in / Sign up

Export Citation Format

Share Document