scholarly journals Annealing-induced effects on structural and optical properties of Cd1−xZnxS thin films for optoelectronic applications

2015 ◽  
Vol 33 (4) ◽  
pp. 677-684 ◽  
Author(s):  
M. Zakria ◽  
Taj Muhammad Khan ◽  
Abbas Nasir ◽  
Arshad Mahmood
Keyword(s):  
Thin Films ◽  
Blue Shift ◽  
Ambient Air ◽  
Longitudinal Optical ◽  
Hexagonal Structure ◽  
Longitudinal Optical Phonon ◽  
X Ray Diffraction ◽  
Phonon Modes ◽  
Different Temperatures ◽  
Xrd Studies

AbstractCd1−xZnxS thin films of variable compositions (x = 0.2, 0.4, 0.6, 0.8) were deposited on glass at room temperature by thermal evaporation process. The prepared samples were annealed at two different temperatures (300 °C, 400 °C) for 1 hour in ambient air. The effects of post-annealing on the structural and optical characteristics were investigated using X-ray diffraction (XRD), spectrophotometry, and Raman spectroscopy (RS) methods. XRD studies suggested that the annealed and as-deposited samples belong to wurtzite structure for all Zn concentrations with a preferential orientation along (002) plane. Spectrophotometry analysis of the samples revealed that the energy band gap decreased with annealing temperature. RS investigated different phonon bands and crystalline phases. Two longitudinal optical phonon modes (1-LO, 2-LO) corresponding to monophase hexagonal structure were observed for all Cd1−xZnxS samples. The observed red-shift and anti-symmetrical nature of the 1-LO phonon mode can be associated with annealing, while the overall blue-shift, except for x ⩽ 0.6, was caused by the structural disorders in periodic Cd atomic sub-lattices and broken translational symmetry. The spectroscopic results were strengthened by the XRD studies and their results are consistent.

Effect of Cd Substitution on Structural and Optical Properties of Zn1-xCdxSe Thin Films

2021 ◽  
Vol 1039 ◽  
pp. 382-390
Author(s):  
Arej Kadhim ◽  
Mustafa Kadhim ◽  
Haslan Abu Hassan
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Longitudinal Optical ◽  
Raman Shift ◽  
Longitudinal Optical Phonon ◽  
Phonon Modes ◽  
Elemental Ratios ◽  
X Ray ◽  
Cdse Thin Film ◽  
Yellow Region

In this research, Zn1-xCdxSe alloys (x from 0 to 1) were synthesized by solid-state microwave (SSM) method of producing thermally evaporated thin films. The cubic structure and the elemental ratios of the films were studied using X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The optical characterizations of the as-deposited film in terms of the energy band gap (Eg), photoluminescence (PL), and Raman shift spectra were conducted at the room temperature. The Eg values for the thin films from ZnSe to CdSe were 3.4 to 1.7 eV, respectively. The PL orange emission for ZnSe thin film at 565 nm, whereas 590 nm in the yellow region for CdSe thin film. From Raman shift spectra, the two longitudinal-optical phonon modes (1LO and 2LO) at 240, and 490 cm-1 are assigned for the ZnSe and CdSe thin films.

scholarly journals Growth Temperature Dependence of Sol-Gel Spin Coated Indium Nitride Thin Films

2019 ◽  
Vol 290 ◽  
pp. 153-159 ◽  
Author(s):  
Zhi Yin Lee ◽  
Sha Shiong Ng ◽  
Fong Kwong Yam ◽  
Zainuriah Hassan
Keyword(s):  
Thin Films ◽  
Growth Temperature ◽  
Indium Nitride ◽  
Sol Gel ◽  
Longitudinal Optical ◽  
Longitudinal Optical Phonon ◽  
Phonon Modes ◽  
Reflectance Measurement ◽  
Ir Reflectance ◽  
Coating Method

The study highlights the effects of growth temperatures ranging from 500 to 650 °C on the properties of indium nitride (InN) thin films prepared by sol-gel spin coating method followed by nitridation, also, the growth mechanism was studied in depth. The findings revealed that the InN crystal growth was promoted at the growth temperature of 600 °C, by which the crystalline quality of the deposited thin films was improved and the densely packed InN grains were formed. However, thermal decomposition of InN was observed at increasing temperature to 650 °C. Apart from that, the infrared (IR) reflectance measurement shows the presence of transverse and longitudinal-optical phonon modes of wurtzite structure InN. These vibrational modes were found to be slightly shifted from the theoretical values as a result of the incorporation of oxygen contamination in the deposited thin films.

Effects of Nitridation Temperatures on Gallium Nitride Thin Films Formed on Silicon Substrates

2014 ◽  
Vol 895 ◽  
pp. 57-62
Author(s):  
Chee Yong Fong ◽  
Sha Shiong Ng ◽  
Fong Kwong Yam ◽  
Abu Hassan Haslan ◽  
Hassan Zainuriah
Keyword(s):  
Thin Films ◽  
Optimal Growth ◽  
Longitudinal Optical ◽  
Longitudinal Optical Phonon ◽  
Silicon Substrates ◽  
Phonon Modes ◽  
Si Substrates ◽  
Coating Method ◽  
Nitridation Temperature

In this article, GaN thin films were successfully grown onp-type silicon (p-Si) substrates with orientation (100) through spin coating method followed by nitridation in ammonia ambient at various temperatures (750 °C, 850 °C, and 950 °C). The morphology of the GaN thin films were performed by using field-emission scanning electron microscopy. The results showed that the grain size increases with increasing nitridation temperature from 750 °C to 950 °C. Optical analysis of the GaN thin films was performed using Fourier transform infrared spectroscopy. It was confirmed from the results that the reflectance intensity of the transverse optical and longitudinal optical phonon modes of wurtzite GaN increases with increasing nitridation temperature. All the measured results show that nitridation temperature plays a very important role in improving the quality of the GaN thin films. Finally, the results revealed that the 950 °C was the optimal growth nitridation temperature for synthesizing GaN thin film.

Growth study of epitaxial FexZn1−xF2 thin films

2001 ◽  
Vol 16 (6) ◽  
pp. 1769-1775 ◽  
Author(s):  
J. McChesney ◽  
M. Hetzer ◽  
H. Shi ◽  
T. Charlton ◽  
D. Lederman
Keyword(s):  
Thin Films ◽  
Film Growth ◽  
Magnetic Phase Diagram ◽  
Epitaxial Thin Films ◽  
X Ray Diffraction ◽  
Growth Study ◽  
Lattice Match ◽  
Different Temperatures ◽  
Bulk Single Crystals ◽  
The Ideal

The FexZn1−xF2 alloy has been shown to be a model system for studying the magnetic phase diagram of dilute magnets. Whereas the growth of bulk single crystals with fixed Zn concentrations is difficult, the thin film growth is comparatively simpler and more flexible. To gain an understanding of the growth of FexZn1−xF2 films, a method was developed to grow smooth films at fixed concentrations. This was done by depositing a MgF2 buffer layer on MgF2(001) substrates and then depositing FeF2 and ZnF2 [001]-orientated epitaxial thin films at different temperatures. Surprisingly, the lattice spacing depends strongly on the growth temperature, for 44-nm-thick FeF2 films and 77-nm-thick ZnF2 films. This indicates a significant amount of stress, despite the close lattice match between the films and the MgF2 substrate. Thick alloy samples (approximately 500 nm thick) were grown by co-evaporation from the FeF2 and ZnF2 sources at the ideal temperature determined from the growth study, and their concentration was accurately determined using x-ray diffraction.

Structural and Surface Characteristics of CuO and Pt/CuO Nanostructured Thin Films

2021 ◽  
Vol 14 (5) ◽  
pp. 419-424
Keyword(s):  
Thin Films ◽  
Optical Fibers ◽  
Structural Information ◽  
Surface Characteristics ◽  
X Ray Diffraction ◽  
Phonon Modes ◽  
Silar Method ◽  
Nanostructured Thin Films ◽  
Average Grain Size ◽  
Sem Micrograph

Abstract: The most prominent and utilizable platinum-coated copper Oxide nanostructured thin films are prepared using the SILAR method. Their structural properties have been studied using X-ray diffraction (XRD) and Raman spectroscopy. XRD pattern reveals the phase purity and crystallinity of CuO nanostructures. The average grain size estimated from XRD gives diameters in the range of 14 - 27 nm. Raman spectra explain the structural information of CuO and Pt/CuO nanostructured thin films, in which the peaks observed at 328 cm-1, 609.32 cm-1 and 1141.77 cm-1 are the different phonon modes of CuO. The peak at 2136 cm-1 provides strong evidence for the formation of platinum on CuO nanostructures. The SEM micrograph confirms the floral morphology, which is composed of nano petals. From the observed morphology, it is observed that the deposited thin films such as CuO and Pt/CuO will give interesting applications to our society by being self-cleaning agents, photocatalysts, semiconductor devices, optical fibers, … etc. Keywords: CuO, Pt/CuO, Structural analysis, SILAR, Crystallinity.

Structural, optical and other spectral studies of transition metal Ti4+-doped Zn-Cd oxide nanomaterials

2020 ◽  
Vol 34 (06) ◽  
pp. 2050033 ◽  
Author(s):  
Mohd Saleem ◽  
S. Tiwari ◽  
M. Soni ◽  
N. Bajpai ◽  
Ashutosh Mishra
Keyword(s):  
Sol Gel ◽  
Relaxation Times ◽  
Hexagonal Structure ◽  
Spectral Studies ◽  
X Rays ◽  
X Ray Diffraction ◽  
Phonon Modes ◽  
Spectroscopy Analysis ◽  
Auto Combustion ◽  
High Dielectric

Titanium ([Formula: see text])-doped nanoparticles of the type [Formula: see text] [[Formula: see text], [Formula: see text]] are reported in this study. The samples were synthesized by citric acid assisted sol–gel auto combustion (SGAC) method. The samples are characterized by X-ray diffraction (XRD), Raman, Field emission scanning electron microscopy (FESEM), Energy dispersive analysis of X-rays (EDAX) and Fourier transform infra-red (FTIR) techniques for structural studies. Further, for optical properties, UV-Vis technique has been used. In addition, samples were studied for dielectric properties. Room-temperature XRD data study reveals the sample formation with wurtzite hexagonal structure exhibiting space group [Formula: see text]mc also confirmed from Rietveld refinement of XRD data. Raman spectra displays characteristic active phonon modes in pristine [Formula: see text] and doped [Formula: see text]. UV-Vis diffused reflectance spectroscopy analysis infer bandgap values of 3.14 and 3.12 eV for [Formula: see text] and [Formula: see text], respectively. The dielectric studies confirmed high dielectric constant for [Formula: see text] compared to pristine [Formula: see text]. A non-Debye character with spread of relaxation times was witnessed from impedance study.

LUMINESCENT PROPERTIES OF SOL-GEL DEPOSITED Eu:TiO2 THIN FILMS

2001 ◽  
Vol 15 (17n19) ◽  
pp. 769-773 ◽  
Author(s):  
M. GARCIA-ROCHA ◽  
A. CONDE-GALLARDO ◽  
I. HERNANDEZ-CALDERON ◽  
R. PALOMINO-MERINO
Keyword(s):  
Thin Films ◽  
Sol Gel ◽  
Luminescent Properties ◽  
X Ray Diffraction ◽  
Si Substrates ◽  
Glass Substrates ◽  
Corning Glass ◽  
Different Temperatures ◽  
Hecd Laser

In this work we show the results on tile growth and optical characterization of TiO 2 thin films doped with Eu atoms. Eu:TiO2 films were grown at room temperature with different Eu concentrations by sol-gel on Si Corning glass substrates. A different crystalline structure is developed for the films deposited on Corning glass than those deposited on Si as observed from x-ray diffraction experiments. Room and low temperature photoluminescence (PL) was measured by using two different lines (325 and 442 nm) of a HeCd laser. A strong PL signal associated to the 5 D 0→7 F 2 transition from Eu +3 was observed. A better emission was obtained from those films deposited on Si substrates, Finally, the evolution of the PL signal is studied when the samples are annealed at different temperatures in O 2 atmosphere.

Electron-Phonon Scattering in GaN/AlN and GaAs/AlAs Quantum Wells

1997 ◽  
Vol 482 ◽  
Author(s):  
T. F. Forbang ◽  
C. R. McIntyre
Keyword(s):  
Quantum Wells ◽  
Optical Phonon ◽  
Phonon Spectrum ◽  
Phonon Scattering ◽  
Relaxation Times ◽  
Longitudinal Optical ◽  
Longitudinal Optical Phonon ◽  
Phonon Modes ◽  
Optical Phonon Scattering ◽  
Electron Phonon Scattering

AbstractWe have studied the effects on the phonon spectrum and on the electron-longitudinal optical phonon scattering in GaN/AlN and GaAs/AlAs quantum wells. Phonon modes and potentials have been calculated for both systems. Results for emission due to electroninterface phonons interactions are presented. We will discuss the implications for relaxation times and electron mobility due to modified LO-phonon scattering in both systems.

Electrochemical Deposition and Characterization of Cd-Fe-Se Thin Films

2009 ◽  
Vol 68 ◽  
pp. 69-76 ◽  
Author(s):  
S. Thanikaikarasan ◽  
T. Mahalingam ◽  
K. Sundaram ◽  
Tae Kyu Kim ◽  
Yong Deak Kim ◽  
...  
Keyword(s):  
Thin Films ◽  
Hexagonal Structure ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Iron Selenide ◽  
Glass Substrates ◽  
Diffraction Patterns ◽  
Cadmium Iron Selenide ◽  
Deposited Films

Cadmium iron selenide (Cd-Fe-Se) thin films were deposited onto tin oxide (SnO2) coated conducting glass substrates from an aqueous electrolytic bath containing CdSO4, FeSO4 and SeO2 by potentiostatic electrodeposition. The deposition potentials of Cadmium (Cd), Iron (Fe), Selenium (Se) and Cadmium-Iron-Selenide (Cd-Fe-Se) were determined from linear cathodic polarization curves. The deposited films were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive analysis by x-rays (EDX) and optical absorption techniques, respectively. X-ray diffraction patterns shows that the deposited films are found to be hexagonal structure with preferential orientation along (100) plane. The effect of FeSO4 concentration on structural, morphological, compositional and optical properties of the films are studied and discussed in detail.

THE INFLUENCE OF SYNTHESIZING TEMPERATURES ON THE PROPERTIES OF THE Cu/Sn/ZnS PRECURSOR THIN FILMS

2015 ◽  
Vol 22 (01) ◽  
pp. 1550009
Author(s):  
YA MING SUN ◽  
DONG LONG ◽  
XIANG CHENG MENG ◽  
ZHONG HUA ◽  
BO LI ◽  
...  
Keyword(s):  
Thin Films ◽  
Soda Lime ◽  
Soda Lime Glass ◽  
Wave Band ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Different Temperatures ◽  
Microstructure Morphology ◽  
Uv Visible ◽  
Precursor Thin Film

Cu 2 ZnSnS 4 thin films were prepared on soda-lime glass by sulfurization of the Cu / Sn / ZnS precursors. The microstructure, morphology and optical properties of the films were investigated by X-ray diffraction (XRD), Raman scattering (Raman), scanning electron microscopy (SEM) and UV-visible spectrophotometer (UV-Vis). The SEM images of the precursor and the thin films annealed at different temperatures are very different due to their different surface products. The absorption spectrum shifts to high-wave band region with increasing annealing temperatures. The precursor thin film annealed at 500°C for 2 h forms a single CZTS phase with kesterite structure and the bandgap is estimated to be 1.54 eV.

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