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The current work focuses on working a comparison between two solar cells made with the combination, n-TiO2/p-CuO, and n-TiO2/p-Cu2O devices. The structural, optical, and photovoltaic characteristics were detailed. In the optical section, the optical measurements for the TiO2 (120 nm), CuO (200 nm), and Cu2O (200 nm) thin films were illustrated, and then the energy of optical transition was calculated based on the Tauc formula for each layer. The direct optical gap energies of TiO2, CuO, and Cu2O thin films are 3.24, 1.77, and 2.18 eV, respectively. The front contact electrode in both systems is an ITO- coated glass layer, while the back contact electrodes are Pt, Ni, Au, Co, Ag, Cu, Al, and Mo. The effect of various metals as back contact electrodes on the photovoltaic characteristics of fabricated devices was investigated. The optical and structural characteristics showed the superiority of the fabricated device n-TiO2/p-CuO over the fabricated device n-TiO2/p-Cu2O.

Significant effort has been devoted in this work to convert bare glass substrate with high transmittance, into reflective layers to know its suitability for modern applications. The glass substrate has been carefully chosen for its durability, high permeability, and ability to withstand any external stresses as a result of the accumulation of layers that reduce its permeability to convert it with the thin films coated on it into reflective materials. In parallel, the thin layer to be coated on the substrate is selected from films that can withstand external influences and their great optical properties, not to mention that they are cheap and can produce highly reflective surfaces. The optical measurements (transmittance and reflectance spectra) have been performed in the UV, Vis and NIR regions of the spectrum, that is, in the range between 300 and 1200 nm. Such measurements have been made for the bare glass substrate, the glass substrate with the Al (top side), and the glass substrate with Ag on it (bottom side), and then the optical measurements have been made for the three layers. The corresponding optical parameters of each layer have been calculated and ultimately a reflective layer with high electrical conductivity and excellent optical properties has been obtained that can be adapted for different application purposes.

The main focus of this framework is the preparation of CdTe nanocrystalline thin films (~120 nm) on single crystal p-Si wafers (270 μm) with Miller index (100) using thermal evaporation. Then, the In/n-CdTe/p-Si/Al solar cell was successfully fabricated. The dark I–V characteristics for the fabricated solar cell have been determined in range of 300–375 K and an applied voltage range of − 2 to 2 V. The fabricated solar cell's behavior was thoroughly explained. As a result, the important parameters for the fabricated solar cell such as the rectification ratio $${\text{RR}}$$ , the junction resistance $$R_{{\text{J}}}$$ , ideality factor of solar cell n, the shunt resistance $$R_{{{\text{sh}}}}$$ , the series resistance $$R_{{\text{s}}}$$ , the barrier height created at the interface between the CdTe thin film and the p-Si wafer $$\phi_{b}$$ , the energy of trap level $$E_{{\text{t}}}$$ and the activation energy of carriers’s recombination in the depletion region $$\Delta E$$ were determined. Finally, the Poole–Frenkel $$\beta_{{{\text{PF}}}}$$ and Schottky $$\beta_{{\text{S}}}$$ parameters were computed.

A widespread analysis of the structural, optical, electronic and electrical properties of Se80Ge20-xBix with (x = 0, 5, 10, 15 and 20 at.%) glasses were carried out. The bulk materials of the studied films have been prepared utilizing the usual melt quench procedure. Thus, the thin film has been deposited under a vacuum of 10–5 Torr on cleaned glass substrates by thermal evaporation. The supreme purpose of this research is to highlight the role of adding bismuth to the films studied as a regulator and controller for the linear and nonlinear parameters. The thickness of the studied thin films has been mathematically determined by the methods of Swanepoel. Using logarithmic functions, it has been proven that the electron transport mechanism between the valence and conduction bands is an allowed indirect transition. Linear optical parameters, dielectric constants and also dispersion parameters have been calculated. The energy-loss functions (VELF and SELF) were discussed. The effect of Bi concentration in the studied thin films on the linear and nonlinear optical properties is determined based on the optical measurements (transmittance and reflectance spectra). The optical bandgap decreases with increasing Bi concentration; while the tail energy portrays an opposite behavior. Linear optical and electrical parameters are found significantly affected by the change of Bi concentration. In contrast, the nonlinear optical parameters have been computed utilizing (H. Ticha and L. Tichy) and Boling formula. Energies of Plasmon, Penn and Fermi and the electronic polarizability have been determined. Furthermore, the DC electrical conductivity has been studied as a function of both temperature in the thermal range from 300 to 500 K and also Bi concentration. In the extended and hopping regions, the activation energy and pre-exponential factor were extracted from the slopes and intercepts of straight lines. It has been found that increasing Bi content is controlled the electrical parameters and reduces the activation energies in the regions of the extended and the hopping states.

Optical properties of amorphous Se65−xAs35Sbx thin films with different compositions (x = 0, 2, 4, 6, 8 and 10 at%) deposited by evaporation technique have been investigated by measuring transmission (T) and reflection (R) in the wavelength range 400–2500 nm. An optical characterization method for uniform films based on Swanepoel’s method has been employed to extract the refractive index n and film thickness d, with high precision (better than 1%). The calculated thickness for all thin films was about 1 µm. In addition, the absorption coefficient was evaluated in the strong absorption region of T and R. The possible optical transition in these films is found to be allowed indirect transition with energy gap $$E_{g}^{\text{opt}}$$ decreases from 1.72 to 1.53 eV with increasing Sb content at expense of Se. The chemical bond approach has been applied to explain the decrease of the optical gap with increasing Sb content. The dispersion and oscillator energies were analyzed using the concept of the single oscillator by Wemple and Di-Domenico. The nonlinear refractive index was calculated and found to be increase with increasing Sb content.

Different compositions of as-obtained As40S60-xSex thin films (x = 0 at.%, 20 at.%, 40 at.%, and 60 at.%) with fixed thicknesses were deposited by a thermal evaporation technique. Inheterogeneities of thin-film thickness is a problem that includes significant errors of optical calculations unless there is an optical model that prevents these errors, and the consequent gross errors, in the measurement of optical constants. If not taken into account, this may lead to rather large calculated values for the absorption coefficient or the incorrect presence of the absorption-band tail, as well as to significant errors in the calculated values of the refractive index and film thickness. The optical properties of As40S60-xSex thin films have been determined utilizing measurements of the optical transmission spectra. Owing to the shrinking of the transmission spectra in both the medium and strong absorption regions, we have resorted to applying the optical wedge model for the determination of the film thickness with high precision that equals approximately 725 nm. This paper therefore presents formulae for the transmittance spectrum of a thin dielectric film of selected thickness covering a thick, non-absorbing substrate as well as its upper and lower envelopes. The effect of the content variation on the interference fringes of the transmittance spectrum is analyzed in detail. The electrical properties of the As40S60-xSex thin films have been studied in terms of measuring the temperature-dependent AC conductivity. Both the dielectric constants and dielectric modulus were investigated and are discussed for applications in optoelectronic devices. The change in electrical properties of As40S60-xSex thin films has been interpreted in terms of changed morphological and structural properties. The ratios of the elements were analyzed by comparing them with the actual weight ratios of the bulk material using EDX technology, in addition to the assessment of the Amorphic structure and composition characteristics of the films examined by the x-ray and scanning electron microscopy.

The structural, optical, electrical and photoelectric properties of n-type CdS1−xSbx layers at varied Sb doping concentrations (x = 0, 0.2, 0.4 and 0.6 at.%) were studied. The melt quenching process was used to generate the bulk form, whereas the thin layers were formed using the thermal evaporation method. To fabricate the Al/n-(CdS:Sb)/p-Si/Pt solar cell, pure CdS and antimony-doped CdS layers of up to 200 nm thickness (n-type side) were deposited on a single-crystallized silicon glass substrate (2 mm) with the Miller's directions (1 0 0). The fabricated solar cells' dark and illuminated current density–voltage (J–V), the power–voltage (P–V) and the capacitance–voltage (C–V) characteristics were thoroughly studied. As well, the open-circuit voltage, the short-circuit current, the fill factor and the power conversion efficiency (PCE) for the studied solar cell were computed. When the antimony ratio is 0.6 at.%, the maximum power conversion efficiency is 30.56%, with the main parameters: Jsc = 26.27 mA/cm2, Voc = 0.84 V, and FF = 0.692. In the instance of using the manufactured devices as detectors, the responsivity and quantum efficiency in the spectrum range of (100–1000 nm) were determined.

Transparent conductive thin films require multilayer coatings involving metals and dielectrics with high refractive indices. Radiofrequency (RF) magnetron sputtering technique was used to accurately fabricate the SiO2/Ag/ZnO multilayers on the corning glass substrates at 298 K to be used in Concentrating Solar Power (CSP) reflectors, solar cell, and photovoltaic applications. This method optimizes coating processes in a uniform, homogeneous manner, resulting in improved optical and electrical properties, thermal endurance, and long-term stability. The technique was used to synthesize highly translucent and conductive multilayers. The structural, optical, and electrical properties as a function of temperature in the range from 25 °C to 450 °C were detailed. The crystallite size (D cry ), lattice microstrain (ε), dislocation density (δ), and crystallites per unit surface area (N) were calculated. The values of (D cry ) increased while the other parameters decreased with increasing temperature. The linear optical parameters were calculated. The optical results demonstrated that temperature had an impact on the studied multilayers’ optical properties. The dielectric constants, the loss factor, the AC electrical conductivity, the exponential factor, and the activation energy for the dominant conductivity mechanism were all calculated using the capacitance and conductance pathways.

The present work investigates the structural parameters of As40S45Se15 glassy alloy and optical properties of its thin films. As40S45Se15 thin films with different thickness (d = 120, 350, 500, 700, 850 and 1000 nm) have been deposited on glass substrates. The association of optical properties with changes in thickness of As40S45Se15 thin films was investigated in the spectral range of transmittance between 400 and 2500 nm. The thin films thickness was calculated using Swanepoel method. The optical constants, dielectric constants, dispersion parameters were computed. The analyses of the absorption spectra of As40S45Se15 thin films indicate the existence of an indirect optical transition mechanism. With increasing the films thickness, the absorption coefficient and optical bandgap were decreased, while Urbach energy, the values of refractive index (n) and the extinction coefficient (kex) were increased. The dispersion of the refractive index is described using the Wimple–DiDomenico (WDD) single oscillator model and the dispersion parameters were computed as a function of thickness films. The optical constants, optical dielectric constants, optical conductivity, electrical susceptibility, and non-linear refractive index were investigated and discussed.

This framework focuses mainly on a detailed study of the pre-crystallization criteria that characterize the As40S45Se15 glassy alloy in various heating rates ranging from 5 to 40 (K/min) by Differential Scanning Calorimetry (DSC). These criteria aim to clarify the relationship of the tendency of glass-forming by the heating rate for the investigated glassy alloy. The crystallization parameters were calculated using different methods.The activation energy of crystallization Ec(χ) as a function of conversion (χ) was obtained using the iso-conversional models of Flynn–Wall–Ozawa (FWO), Starink and Kissinger–Akahira–Sunose (KAS). The results show a slight increase of Ec(χ) with conversion (χ) which accounts for a single-step mechanism controlling the crystallization process. Moreever, the conversion dependence of the Avrami exponent n(χ) show an increase with conversion (χ), average values of n(χ) can be accounted for two and three-dimensional crystal growth with heterogeneous nucleation. On the other hand, the fitting of the experimental DSC data to the calculated DSC curves indicated that the crystallization process of the studied glasses cannot be satisfactorily described by the Johnson–Mehl–Avrami (JMA) model. On the contrary (SB) model is more suitable to describe the crystallization process for the studied of As40S45Se15 Alloy. Finally, the crystalline structure of the study sample was recognized by X-ray diffraction (XRD) and electron scanning microscope (SEM).

The present framework is primarily concerned with the optical properties of As40Se60-xSnx thin films. The bulk form has been synthesized by the melt quenching technique. The thin films have been prepared by thermal evaporation technique. The XRD and the SEM techniques showed the non-crystalline nature of the prepared glasses. The refractive index n, energy gap, energy loss functions and other optical constants have been determined. The findings refer to increase of the refractive index of thin films with the increase of Sn content. The energy gap decreases to 1.4 eV with the increasing of Sn content for the investigated films. Further explanation of the physical characteristics of the investigated films made following the approach of chemical bond. Additionally, the optical dispersion dn/dλ, phase velocity vp and group velocity Ug have been discussed in detail.

Here we report on studying the electronic and optical material properties of the technologically-relevant material indium tin oxide (ITO) as a function of thermal annealing. In this work, ITO powder has been prepared utilizing solid-state reaction methods. An electron beam gun technology has been used to prepare a ITO film (325 nm). The ITO window layer has been investigated at various temperatures. The effects of absolute temperature on the structural, optical, and electrical properties of the prepared ITO thin film layer are investigated. The energy band type corresponding to the orbital transitions has been determined, and the energies of the orbital transitions have been calculated in the Tauc region, HOMO/LUMO gap, and charge transfer gap. In additions, the exciton and Urbach energies have been computed. It has been found that these energies increase with increasing the annealing temperature, except for Urbach's energies which behave differently. Thin-film quality coefficient, surface resistance, and thermal emission in addition to the angle of refraction as a function of wavelength, have been determined., 32 pages, 18 figures

In this framework, the ZnSe layer was prepared via the well-known thermal evaporation method at various thicknesses. The thicknesses of the ZnSe layer were monitored by the quartz crystal monitor type (FTM4, Edwards). The influence of ZnSe film’s thickness on the structure, optical and electrical properties were studied. Using XRD patterns, the structural parameters of the ZnSe layer have been calculated. It is observed that the crystallite size increases as the film thickness increases, but the lattice strain decreases. SEM measurement results show that as the thickness of the ZnSe film increases, the grain size improves. The electrical properties of ZnSe films at various thicknesses have been measured via a standard four-point probe method. It can be noticed that as the ZnSe film’s thickness increases, the electrical conductivity also increases. This means that ZnSe film with higher electrical conductivity will be more suitable for the high-efficiency ZnSe/CdTe solar cell. In a higher absorption region for both T (λ) and R (λ), the absorption coefficient has been determined, and thus the optical energy gap, which is increased from 2.62 to 2.91 eV. At the same time, the effect of the ZnSe layer with different thicknesses on the performance of the ZnSe/CdTe solar cell was discussed. The figure of merit has been computed to determine the quality of the thin films. The parameters of the hetero-junction have been measured, such as the correction ratio, which is improved by increasing the film’s thickness. The junction resistance and parasitic resistance were also calculated which is decreased with increasing of the thickness film, thereby improving the performance of fabricated ZnSe/CdTe solar cell.

Se50Te50 alloy has been successfully fabricated utilizing the common melt quench technique. The Se50Te50 film was deposited onto a well-cleaned glass substrate at 298 K by thermal evaporation method. The film's thickness (~500 nm) was monitored by a quartz crystal monitor. Dielectric permittivities ( e ′ , e ″ ), dissipation factor, tan ( δ ) , conductivity, σ A C , modulus ( M ′ , M ″ ) and impedance parts ( Z ′ , Z ″ )were determined based on the capacitance-voltage (Cm–V) and conductance-voltage (Gm/ω-V) measurements. AC electrical conductivity has two contributes, electronic and ionic conductivity. The main structural characteristics were checked utilizing EDAX, X-ray and SEM measurements.

This framework focuses fundamentally on sheet resistance, Rs, measurements for the As40S60−xSex thin films with [(0≤ x ≥60) at.%] for thickness of the film and heating rate of 1000 nm and 5 K/min, respectively. Then, we can adapt these measurements to study the thermal and electrical properties by which we can reduce the time and effort spent. The thermal and electrical analysis in this work appears in a new format without the need for a procedure to calculate the thermal measurements from bulk material of the studied sample. The same is true for electrical properties where electrical measurements need not be necessarily carried out. In this work, we will focus first on obtaining the sheet resistance, Rs of thin films whose surface thickness is equal to 1000 nm for chalcogenide As40S60−xSex thin films with [(0≤ x ≥60) at.%] at a heating rate of 5 K/min, in the temperature range from 300 to 435 K. This range was sufficient to highlight on two important regions in the sheet resistance curve and through the derivation of sheet resistance as a function of temperature, there was clear evidence of one crystallization region for the studied samples. Second, the thermal data we obtained were used to complete the thermal calculations and then the electrical calculations. The activation energies of crystallization were evaluated. The nucleation and growth order parameter n, and the dimension order parameter m, were also computed and discussed. The activation energy, Ec, and Avrami index, n, were obtained by analyzing the data via JMA methods. The results indicated that the transformation from amorphous to crystalline phases is a complex process that includes different mechanisms of nucleation and growth. The change of activation energy with volume of crystalline fraction was determined. The crystalline phases for the as-deposited and annealed films were identified using X-ray diffraction (XRD). The electrical results of the investigated sample appear in two types of conduction channels which contribute to two conduction mechanisms in the crystallized region. In the extended and hopping states regions, the activation energies ΔE, two pre-exponential factors $$\sigma_{0} ,$$ $$\sigma_{0}^{*}$$ and other parameters were computed.

In the present framework, the TiO2 thin film at different thicknesses (where d = 100, 120, 140, 160, 180, and 200 nm) has been successfully synthesized using the well-known thermal evaporation technique. The thickness of TiO2 layer has been monitored utilizing the quartz crystal monitor (type-FTM4, Edwards). The effect of TiO2 film’s thickness on the structural, optical, electrical and photovoltaic properties has been investigated. The structural parameters of TiO2 layer such as the lattice strain, e and the crystalline size, D have been computed utilizing the XRD pattern. According to the results of the XRD, it has been found that the crystalline size has been increased while the lattice stress decreased as the thickness of the TiO2 layer increased. The results of SEM have been shown that as the TiO2 film’s thickness increases, the grain size improves. On the other hand, the values of the optical bandgap decreases as the thickness of the film increases. The energy diagram of TiO2 layer and also for the fabricated solar cell have been plotted. The capacitance-voltage (C-V) characteristics have been studied to determine the type of the heterojunction (sharp or gradual). According to such measurements, the built-in-voltage, the width of the depletion region, and the maximum electric field have been extracted. The polarization dependence of an electric field has been investigated. As well, the significant influence of TiO2 layer on optimizing the performance of the TiO2/p-Si solar cell has been also studied. The dark and illuminated current density-voltage (J-V) characteristics for the fabricated solar cell has been studied. The Ohmic, SCLC regions and the transition voltage have been determined. The parameters of the TiO2/P-Si solar cell such as the rectification ratio, RR, the junction resistance and the parasitic resistances have been studied. Furthermore, it has been found that the power conversion efficiency PCF and the fill factor FF of the heterojunction have been increased with increasing the thickness of TiO2 layer. Finally, the temperature dependence of the open-circuit voltage (VOC) has been studied to estimate the activation energy as a function of the thickness of TiO2 layer in the fabricated system.

The scenarios for this work have been summarized in the preparation of the Se50Te50 thin film -(~500 nm)- by thermal evaporation method, then using a mercury lamp with a 150 W/cm2 as a source of ultraviolet radiation. The irradiation process has been carried out in the open air for the Se50Te50 thin film without irradiation and in the UV-treated period between 0.5 and 2.5 h. A thorough study has been carried out which ultimately has been confirmed from it that the irradiation time plays the role of controlling the optical and electrical properties. The energy band type corresponding to the orbital transitions has been determined, and the energies of the orbital transition has been calculated in the Tauc region, HOMO/LUMO gap, and charge transfer gap. In addition to, calculating the exciton and Urbach energies. It has been found that these energies decrease with increasing UV exposure time, except for Urbach's energies, which behave differently. The role of the UV exposure time in controlling many optical constants, dispersion, and dielectric parameters was investigated. Thin-film quality coefficient, the surface resistance, and thermal emission, in addition to the angle of refraction as a function of wavelength, have been determined. As well, the spectral distribution of the molar parameters has been discussed. Finally, the DC electrical conductivity, the activation energy in the extended and hopping state regions, and Mott's parameters have been computed.

In this framework, the bulk sample of Se80S20 has been successfully generated using the common melt quenching method. The main structural characteristics of Se80S20 were checked utilizing EDAX, X-ray, and SEM measurements. The thin film (~500 nm) fabricated from the bulk sample is thermally deposited on a clean glass substrate at 298 K using the evaporation technique. The thickness of the analyzed film has been monitored by a crystal monitor. On the other hand, the dielectric permittivities, dissipation factor, AC electrical conductivity, modulus, and impedance components were determined based on the capacitance-temperature (Cm-T), capacitance-frequency (Cm- ω ), conductance-temperature (Gm-T), and conductance-frequency (Gm - ω ) measurements. AC electrical conductivity, σ A C ( T ) has two contributes, electronic and ionic conductivity. Physical parameters of Se and S elements have been reported. As well, the important electrical parameters such as the power of angular frequency m , the maximum barrier height W m , energy band gap E g , the pre-exponential factor σ ο , the activation energy of the conduction mechanism, E A C in both extended and hopping regions and the relaxation parameters of fresh Se80S20 thin film at different frequencies have been computed. Finally, the behavior of the local state density at the Fermi level has been studied as a function of temperature at different frequencies and also as a function of frequency at different temperatures.

In this framework, a novel Ge20+xSe80-x thin films ~890 nm, with (x = 5, 10, 15, 20, 25, and 30 at. %) were synthesized via thermally evaporation method at 298 K. The elemental ratios of Ge–Se thin films have been checked by EDX analysis and also the amorphous natural was confirmed through X-Ray Diffractometer, XRD. In thin films belonging to the glass chalcogenide, in the case of existence of interference in the optical measurements-namely, transmittance, T and reflectance, R spectra-often the dispersion refractive index, n ( λ ) and the thickness of the thin film, d were computed based on the spectrum of transmittance or reflectance and also the wavelength along with the optical measurements. In this work, the real optical constant n ( λ ) and film's thickness of Ge–Se thin films have been computed utilizing the wavelength measurements of the normal and slightly inclined incidence light solely. Then, the linear optical parameters such as Tauc's energy E g and Urbach's energy E e , the linear imaginary optical constant, namely, absorption index or extinction coefficient k e x , the linear dispersion parameters, namely, the single oscillator energy E o and the dispersion energy E d and the non-linear optical constant or so called the second-order of refractive index n 2 have been determined. The optical dispersion d n d λ , phase velocity v p , group velocity U g , Magneto-Optical Constant or Verdet coefficient V ( λ ) and the positions of the energy levels have been discussed in detail.

Thin films of As40S60-xSex ((0 ≤ x ≥ 60) at. %) have been efficiently synthesized through the process of vacuum thermal evaporation. The present framework analyzes the thin films to determine both optical and electronic parameters as a function of change of Se concentrations. The thickness of the obtained films, d have been mathematically determined utilizing Swanepoel's computations and experimentally via an MII-4 interference microscope with an accuracy of 1%. The thickness of the studied films has been closed to 500 ± 15 nm. Additionally, the optical properties of these films have been scrutinized from the transmittance and reflectance spectra measured by a UV–Vis–NIR spectrophotometer. The transmission spectra, T (λ) of such films have been documented in the spectral region 400–2500 nm. Based on the optical measurements, all of the linear optical constants, the linear optical and dielectric parameters, the linear and non-linear optical susceptibility criteria, and the material dispersion coefficient M ( λ ) have been computed. Besides, the nonlinear refractive index, energies of the electronic polarization have been determined.

This study reports the linear and nonlinear optical and electronic properties of as-prepared and annealed ∼240 nm thick Ge20Te80 films. The optical properties were studied based on the transmittance and reflectance spectra measured by spectrophotometer within the range of 380–1090 nm. The optical absorption data were described by Tauc’s relationship. The refractive index and extinction coefficient were evaluated, and a correlation between the refractive index and the optical bandgap is discussed. The dispersion and oscillator energies were analyzed by the Wemple-DiDomenico concept of the single oscillator. The dielectric constants, the loss tangent, and volume/surface energy loss functions were deduced. The electronic polarizability was computed by three different methods. The optical bandgap of thermally evaporated Ge20Te80 film and films annealed at 373–473 K (amorphous films) exhibit allowed direct and indirect transitions while the films annealed at 523–573 K (crystalline films) exhibits only allowed direct transition. The developments of crystal structure, optical parameters, and the optical conductivity upon thermal annealing, make the Ge20Te80 chalcogenide film candidates for numerous photonic applications.

Freeze dried gum cordia (GC) was obtained from Cordia myxa (L.) fruits through hot water extraction method. Functionally GC presented high water and oil holding capacities with considerable foaming stability. The study was conducted to evaluate the effect of freeze dried GC on functional properties of dough and its possible application as an alternative hydrocolloid in controlling bread staling by replacing 0, 3, 5 and 10% wheat flour. Significantly, higher farinographic water absorption (%) and mixing tolerance index were recorded with subsequent higher gum concentrations. Conversely, dough stability and time to breakdown were negatively affected by GC addition. Similarly, with increased GC levels a declining trend in dough extensibility (mm) and energy (cm2) were determined through Brabender Extensograph, but interestingly 3% GC presented the highest resistance to extension and maximum resistance. A significant (P≤0.05) reduction in bread loaf volume, specific volume, and darker crumb colour was measure...

Chalcogenide Se50Te20S30 thin film of different thickness was deposited using thermal evaporation technique. The thermogram of the chalcogenide bulk Se50Te20S30 was obtained using a differential scanning calorimetry (DSC) with heating rate of 7.5 K/min. The glass transition temperature T g, crystallization temperature T c and peak crystallization temperature T p were identified. The X-ray diffraction (XRD) examination indicates the amorphous nature of the as-deposited film and polycrystalline structure of the thermal annealed ones. The dark electrical resistivity (ρ) measurements were taken in temperature range (300–500 K) and thickness range (200–450 nm). Analysis of the electrical resistivity results revealed two types of conduction mechanisms: conduction due to extended states in the temperature range (T > T c) and variable range hopping in the temperature range (T

Chalcogenide Te40Se30S30 thin films of different thickness (100–450 nm) are prepared by thermal evaporation of the Te40Se30S30 bulk. X-ray examination of the film shows some prominent peaks relate to crystalline phases indicating the crystallization process. The calculated particles of crystals from the X-ray diffraction peaks are found to be from 11 to 26 nm. As the thickness increases, the transmittance decreases and the reflectance increases. This could be attributed to the increment of the absorption of photons as more states will be available for absorbance in the case of thicker films. The decrease in the direct band gap with thickness is accompanied with an increase in energy of localized states. The obtained data for the refractive index could be fit to the dispersion model based on the single oscillator equation. The single-oscillator energy decreases, while the dispersion energy increases as the thickness increases.