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1

Characterisation of the tin oxide conducting film obtained by ultrasonic spray pyrolysis

100%

Nocuń M.

Optica Applicata

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2003

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tom Vol. 33, nr 1

183-190

EN

Tin oxide thin film was obtained by ultrasonic spray pyrolysis technique on a glass substrate using different precursors (SnCl4, SnCl2, SnCl2×2H2O). Tin oxide layers were characterised by optical spectroscopy (UV-VIS), photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) technique. Different precursors used in solution preparation led to differences in morphology, conductivity and growth rate of the tin oxide films.

2

Raman investigation of hybrid polymer thin films

100%

Gnyba M. , Keranen M. , Kozanecki M. , Kosmowski B. B.

Materials Science Poland

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2005

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tom Vol. 23, No. 1

29--39

EN

Raman spectroscopic studies were carried out for hybrid polymer thin films prepared for photonic applications by the sol-gel technology. Our aims were to analyse the ability of the Raman method toestimate the efficiency of the main reactions of the sol-gel process and to provide information about the chemical composition of the films as well as their thickness, profile, and quality. The difficulties in measurement such as low level of Raman signals, difficulties in data analysis caused by the complex structure of the materials, and the influence of interfering signals, are discussed. The application of Raman microscopy for characterising films based on 3-glycidoxypropyl-trimethoxysilane (GPTS), methacryloxypropyltrimethoxysilane (MPTS), and 3-aminopropyl-trimethoxysilane (APTES) is presented. The efficiencies of reactions of inorganic and organic polymerisation were measured and their products have been identified. The influence of the excitation beam wavelength as well as the type of substrate on the Raman spectra was investigated. Moreover, two-dimensional Raman mapping enabled us to record the thickness profiles of the deposited structures and to detect their defects.

3

Effect of Nitridation and Pre-Growth Annealing of the Sapphire Substrate on the Quality of Zinc Oxide Thin Films Grown by RF-Magnetron Sputtering

100%

Baseer Haider M.

Acta Physica Polonica A

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2017

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tom 132

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nr 4

1325-1328

EN

ZnO has attracted much attention due to its wide bandgap (3.2 eV) and high exciton binding energy of 60 meV. These properties make ZnO a highly desirable material for high frequency devices that can work in harsh environment. We have grown ZnO thin films at different temperatures ranging from 100°C to 500°C. We have observed that surface roughness is first decreased with the increase in the growth temperature but then by further increasing the growth temperature beyond 300°C, results in increased surface roughness of the grown samples, whereas grain size of the samples increases with the increase in the growth temperature. Crystalline quality of the films is also improved with the increase in the growth temperature but then degrades by further increase beyond 200°C. We achieved the highest Hall mobility for the ZnO sample grown at 200°C. The optimum growth condition of ZnO thin films on sapphire (0001) in our RF/DC magnetron-sputtering unit were achieved for the films grown at 200°C. Subsequently, we performed pre-growth treatment to the sapphire substrate then grew ZnO films at 200°C. Pre-growth treatment involved heating the substrate at 500°C for about half an hour and then etching the sapphire surface with nitrogen plasma. We have observed that pre-growth heating and nitridation of the sapphire substrate results in bigger grain size whereas no improvement was observed in the crystallinity of the film.

4

Optimization of S:Sn precursor molar concentration on the physical properties of spray deposited single phase Sn2S3 thin films

100%

Srivind J. , Nagarethinam V. S. , Balu A. R.

Materials Science Poland

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2016

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tom Vol. 34, No. 2

393--398

EN

Nanoneedle structured Sn2S3 thin films were prepared by spray pyrolysis technique from aqueous solutions of tin (II) chloride and thiourea, keeping the molar concentrations of S:Sn = 0.01:0.01, 0.02:0.02, 0.03:0.03 and 0.04:0.04 in the starting solutions. XRD studies reveal that all the films exhibit orthorhombic crystal structure with a preferential orientation along the [2 1 1] direction. The peak intensity of the (2 1 1) plane is found to be maximum for the film coated with 0.02:0.02 S:Sn molar concentration which confirms the improved crystalline nature of this film. SEM images depict that the film coated with S:Sn molar concentration 0.02:0.02 exhibit needle shaped grains. The optical band gap exhibits red shift from 2.12 eV to 2.02 eV with an increase in S:Sn precursor molar concentration. Electrical studies show that the films having S:Sn molar concentrations 0.01:0.01 and 0.02:0.02 exhibit minimum resistivity values of 0.238 and 0.359Ω ·cm, respectively.

5

Optical Properties of Polyvinyl Chloride Doped with DCM dye Thin Films

100%

Mohamed A. N. , Tuhaiwer A. S. , Razzaq Z. S.

World Scientific News

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2016

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tom 30

45-56

EN

Optical properties such as absorption coefficients, refractive indices, and extinction coefficients of pure polyvinyl-chloride (PVC) and DCM laser dye doped with PVC thin films where prepared using casting method have been determined in the range between 190-1100nm. Measurement have been performed in pure and doped (PVC). The direct electronic transition and indirect energy gaps were calculated using the behaver of absorption coefficient with wavelength. The direct energy gap was 3.9e.V for pure PVC and 2e.V for doped PVC, but indirect energy gap was 2.4e.V for pure PVC and 1.1e.V for doped. The phonon energy was 1.05e.V for pure PVC and was 0.55e.V for DCM doped with PVC thin film.

6

Study of Ho doped Ag2S thin films prepared by CBD method

100%

Yadu G. , Pateria M. A. , Deshmukh K.

Materials Science Poland

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2020

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tom Vol. 38, No. 1

206--213

EN

Ho doped Ag2S thin films were grown on the glass substrate by chemical bath deposition (CBD) method at room temperature. The bath contained aqueous solution of silver nitrate, thiourea, EDTA, ammonia and holmium nitrate. Silver nitrate was used as a silver (Ag+) ion source; thiourea as sulfur (S−) ion source, EDTA was a complexing agent while ammonia was used to maintain pH, Ho(NO3)3 was taken as a source of Ho ions. The optical absorption edge of undoped (pure) and Ho doped silver sulfide films was determined between 324 nm and 298 nm showing blue shift as compared to bulk Ag2S. Band gaps calculated from Tauc plot also showed an increase in values for doped samples. The increase in band gap indicates reduced particle size in the prepared Ho doped films. The photoluminescence emission peaks were observed at around 578 nm to 601 nm wavelength and excitation peaks were found at 351 nm to 294 nm for undoped and doped films. The SEM micrograph consists of globular ball type and flower type structures observed in the prepared films of Ho doped Ag2S.

7

Influence of deposition temperature on amorphous structure of PECVD deposited a-Si:H thin films

100%

Müllerová J. , Fischer M. , Netrvalová M. , Zeman M. , Šutta P.

Open Physics

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2011

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tom 9

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nr 5

1301-1308

EN

The effect of deposition temperature on the structural and optical properties of amorphous hydrogenated silicon (a-Si:H) thin films deposited by plasma-enhanced chemical vapour deposition (PECVD) from silane diluted with hydrogen was under study. The series of thin films deposited at the deposition temperatures of 50–200°C were inspected by XRD, Raman spectroscopy and UV Vis spectrophotometry. All samples were found to be amorphous with no presence of the crystalline phase. Ordered silicon hydride regions were proved by XRD. Raman measurement analysis substantiated the results received from XRD showing that with increasing deposition temperature silicon-silicon bond-angle fluctuation decreases. The optical characterization based on transmittance spectra in the visible region presented that the refractive index exhibits upward trend with increasing deposition temperature, which can be caused by the densification of the amorphous network. We found out that the scale factor of the Tauc plot increases with the deposition temperature. This behaviour can be attributed to the increasing ordering of silicon hydride regions. The Tauc band gap energy, the iso-absorption value their difference were not particularly influenced by the deposition temperature. Improvements of the microstructure of the Si amorphous network have been deduced from the analysis.

8

Measurement of stress as a function of temperature in Ag and Cu thin films

100%

Prószyński A. , Chocyk D. , Gładyszewski G. , Pieńkos T. , Gładyszewski L.

Optica Applicata

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2005

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tom Vol. 35, nr 3

517-522

EN

Stress measurements of 23 nm copper films and 93 nm silver films on Si (100) have been performed during thermal cycling between RT and 450°C. The changes in stress versus temperature are interpreted. The effects of treatment on microstructure and composition are studied by X-ray diffraction.

9

Photoluminescence of poly(N-vinylcarbazole) thin films deposited by dip-coating technique

100%

Rębarz M. , Dalasiński P. , Bała W. , Łukasiak Z. , Wojdyła M. , Kreja L.

Optica Applicata

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2005

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tom Vol. 35, nr 3

407-412

EN

This paper is concerned with the photoluminescence (PL) study of poly(N-vinylcarbazole) (PVK) thin films deposited on the glass substrate by the dip-coating method. The PL spectra have been measured under steady state excitation (He-Cd laser, 325 nm) in the temperature range from 13 to 300 K. All the samples being studied exhibit strong luminescence in broad temperature range. The main emission PL peak has maximum at 410 nm and is attributed to the excimer emission of PVK. We have observed a small red-shift of this peak with an increase of temperature. In all the films under investigation the thermal quenching of PL has been noticed. This behaviour is determined by the closeness of carbazole groups belonging to neighbouring chains because the interaction between them leads to nonradiative transitions. The PL spectra of PVK thin films annealed under iodine atmosphere have also been investigated. We have observed a decrease of PL for these films. We have concluded that the annealing of PVK under iodine atmosphere induces its degradation.

10

Ti-doped In2O3 transparent conductive thin films with high transmittance and low resistivity

100%

Song Z. , Fu Q. , Li L. , Li L. , An Y. , Wang Y.

Optica Applicata

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2010

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tom Vol. 40, nr 4

751--757

EN

Ti-doped In2O3 thin films have been prepared on glass substrate by radio frequency (RF) sputtering with different sputtering powers (90, 120, 150, and 180 W) at 330 °C. The influence of sputtering power on the structural, electrical and optical properties of the deposited thin films is investigated. The average transmittance of the thin films in the wavelength range of 500-1100 nm is over 90%. Low resistivity of 7.3×10-4 ?cm is also obtained based on our thin films, suggesting that Ti-doped In2O3 is a good candidate for transparent conductive thin film.

11

Impact of the etching time and current density on Capacitance-Voltage characteristics of P-type of porous silicon

100%

Hadi H. A. , Abood T. H. , Mohi A. T. , Karim M. S.

World Scientific News

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2017

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tom 67

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nr 2

149-160

EN

In This paper, electrochemical etching teqniques was using to formation of nano crystalline porous silicon layer on p-type Si substrates. Measurement of capacitance – voltage characteristics at various etching time and current densities were used for calculated built in voltage and type of heterojunction. The built in voltage values were decreased with increasing etching time and current densities for both anisotype Al/PS/p-Si/Al heterojunction. These characteristics are interpreted by assuming the abrupt heterojunction model. The effect of different etching time and current densities on electrical properties of PS have been investigated.

12

Structural and electrical properties of barium titanate (BaTiO3) thin films obtained by spray pyrolysis method

100%

Kumbhar S. S. , Mahadik M. A. , Chougule P. K. , Mohite V. S. , Hunge Y. M. , Rajpure K. Y. , Moholkar A. V. , Bhosale C. H.

Materials Science Poland

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2015

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tom Vol. 33, No. 4

852--861

EN

Barium titanate (BaTiO3) thin films have been prepared using the spray pyrolysis method. The films were deposited onto a glass substrate at varying substrate temperature ranging from 250 to 350 degrees C with the interval of 50 degrees C. The structural, morphological, electrical and dielectric properties of the deposited films have been studied. The X-ray diffraction pattern confirmed the polycrystalline nature of the films with a cubic crystal structure. X-ray photoelectron spectroscopy (XPS) showed a good agreement of the thin films stoichiometry with (BaTiO3). A presence of Ba, Ti and O in the BaTiO3 thin films was observed by energy dispersive X-ray analysis. The scanning electron microscopy (SEM) showed the heterogeneous distribution of cubical grains all over the substrate. The grain size decreased with an increase in substrate temperature. The dielectric constant and dielectric loss showed the dispersion behaviour as a function of frequency, measured in the frequency range of 20 Hz to 1 MHz. The AC conductivity (sigma(ac)) measurement showed the linear nature of obtained films, which confirms conduction mechanism due to small polarons. Impedance spectroscopy has been used to study the electrical behaviour of BaTiO3 ferroelectric thin films. The ferroelectric hysteresis loop has been recorded at room temperature.

13

Structural Characterization of LaCoO3 Thin Films Grown by Pulsed Laser Deposition

100%

Jędrusik M. , Cieniek Ł. , Kopia A. , Turquat C. , Leroux C.

Archives of Metallurgy and Materials

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2020

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tom Vol. 65, iss. 2

793--797

EN

Thin films of crystallized LaCoO3 were grown on Si substrate by Pulsed Laser Deposition at different temperatures (750°C, 850°C and 1000°C). The structural characterization of the LaCoO3 thin films was done by combining several techniques: Scanning Electron Microscopy (SEM), Atomic Force Microscope (AFM), Transmission Electron Microscopy (TEM) and Grazing Incidence X-Ray Diffraction (GIXRD). The thin films crystallized in the expected rhombohedral phase whatever the deposition temperature, with an increase of crystallite size from 70 nm at 750°C to 100 nm at 1000°C, and an average thickness of the thin films of less than 200 nm. At 850°C and 1000°C, the thin films are crack-free, and with a lower number of droplets than the film deposited at 750°C. The grains of LaCoO3 film deposited at 850°C are columnar, with a triangular termination. At 1000°C, an intermediate layer of La2 Si2 O7 was observed, indicating diffusion of Si into the deposited film.

14

Optical properties of AlN layers obtained by magnetron sputtering

100%

Potera P. , Wisz G. , Szyller Ł.

Materials Science Poland

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2018

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tom Vol. 36, No. 4

717--721

EN

The growth of AlN layers on glass substrates using magnetron sputtering method was performed and the grown layers were subjected to optical measurements. Transmission spectra of the layers grown at different content of N2 in the atmosphere were obtained. The transmission spectra as well as energy gap depended on N2 content. The annealing of the layers in air led to transmission changes and influenced energy gap and refractive index values.

15

Investigations of highly conducting and transparent Sc doped ZnO films grown by the sol-gel process

100%

Sharma R. , Shishodia P. K. , Wakahara A. , Mehra R. M.

Materials Science Poland

|

2009

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tom Vol. 27, No. 1

225--237

EN

Highly transparent and conductive scandium doped zinc oxide (ZnO/Sc) films were prepared on Corning glass 7059 substrates by the sol-gel technique. The influence of scandium concentration (0-1.5 wt. %) and annealing temperature (300-500 °C) on the structural, optical and electrical properties was investigated. The average transmittance was found to be above 89% in the visible region. ZnO/Sc film having 0.5 wt. % of Sc and annealed at 400 °C exhibited a minimum resistivity of 3.52×10-4 ohmocm. The surface morphology of these films examined by SEM and AFM revealed formation of nano rods.

16

Optical and Resistance Sensors for Hydrogen Detection in Gas Mixture and Transformer Oil

100%

Bodzenta J. , Burak B. , Jakubik W. , Kochowski S. , Urbańczyk M.

Molecular and Quantum Acoustics

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2001

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tom Vol. 22

29-36

EN

Results of the investigation of thin Pd layers as hydrogen sensors are presented. Two types of sensors are examined - resistance and optical sensors. Changes in measured signal as a function of hyfrogen concentration in hydrogen-nitrogen mixture are registered. The sensor is exposed either directly to the gas mixture or to the transformer oil, through wich the gas mixture passes. The hydrogen concentration in the mixture changes from 0.5% to 4%. Investigated sensors are sensituve enough in this concentration range, in both media. Changes of Pd film properties caused by hydrogen absorption are reversible except a few first exposures to the mixture. Obtained results confirm the possibility of developing simple sensor for detection of hydrogen gas in dissolved in the transformer oil.

17

Perovskite La1-xSrxFeO3 Thin Films Deposited by Laser Ablation Process

100%

Cyza A. , Cieniek Ł. , Kopia A.

Archives of Metallurgy and Materials

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2016

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tom Vol. 61, iss. 2B

1063--1067

EN

The aim of the research was to investigate the influence of strontium on the structure of thin films La1-xSrxFeO3 (x = 0; 0,1; 0,2). The LaFeO3 and Sr-doped LaFeO3 films were produced by pulsed laser deposition (PLD) on Si (100) substrate using the Nd-YAG (λ = 266 nm) laser. SEM, AFM and XRD methods were used to characterize the structure and morphology of the thin films. X-Ray Diffraction analysis showed only the LaFeO3 phase in the undoped thin film and the La0.9Sr0.1O3 and La0.8Sr0.2O3 phases in thin films doped by Sr. The mean crystallite size, calculated by Williamson-Hall method, was smaller (of the order of 18 nm) in films doped by Sr. SEM analysis showed small droplets in thin films doped by Sr. Highly developed surface layer was observed using the AFM microscope for thin films doped by Sr.

18

Some remarks on the paper "Optimization of S:Sn precursor molar concentration on the physical properties of spray deposited single phase Sn2S3 thin films" by J. Srivind, V.S. Nagaretthinam, A.R. Balu [Mater. Sci.-Poland, 34 (2016), 393 – 398]

100%

Tomaszewski P. E.

Materials Science Poland

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2020

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tom Vol. 38, No. 3

400--401

19

Drying of binary thin film polymeric coatings: an experimental study

100%

Katariya J. , Arya R. K.

Polish Journal of Chemical Technology

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2012

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tom Vol. 14, nr 4

83-87

EN

Four binary polymer -solvent systems, poly(styrene)-tetrahydrofuran, poly(styrene) - p-xylene, poly(methyl methacrylate) - ethylbenzene and poly(methyl methacrylate) - tetrahydrofuran, systems have been studied. It has been observed that thicker coatings will retain a higher amount of the residual solvent as compared to thinner coatings. In the case of poly(styrene)-tetrahydrofuran coating residual solvent remaining within the coatings were 9.09% and 4.74% for the coatings of the thicknesses of 967 micron and 559 micron, respectively. Similar trends were also observed in the case of poly(methyl methacrylate)-ethylbenzene, poly(methyl methacrylate)-tetrahydrofuran, and poly(styrene)-p-xylene systems.

20

Laser modification of the electrical properties of vanadium oxide thin films

100%

Stefanovich G. B. , Pergament A. L. , Chudnovskii F. A. , Kikalov D. O.

Opto-Electronics Review

|

1999

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tom Vol. 7, No. 2

131-134

EN

The effect of laser irradiation on amorphous films of anodic vanadium oxide was studied using a YAG:Nd³⁺ laser at wavelength 1.06 µm. Irradiation was found to lower the electrical conductivity of the oxide films and modify significantly the parameters of electroforming and switching in metal/oxide/metal sandwich structures. The threshold energy for laser modification was measured to be ~ 0.3 mJ/cm². It is shown that the changes of the electrical properties are associated with structural (crystallization) and chemical (in particular, the reduction V₂O₅ → VO₂) transformations and that non-thermal photo-stimulated effects play an important role in the laser modification of the vanadium oxide thin films.