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1

Effect of thermal annealing on structural and optical properties of In doped Ge-Se-Te chalcogenide thin films

Singh Pravin Kumar, Tripathi S. K., Dwivedi D. K.

Materials Science Poland

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2019

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Vol. 37, No. 4

554--562

EN

Thin films of Ge10–xSe60Te30Inx (x = 0, 2, 4 and 6) were developed by thermal evaporation technique. The annealing effect on the structural properties of Ge10–xSe60Te30Inx (x = 0, 2, 4 and 6) films has been studied by X-ray diffraction (XRD). The XRD results indicate amorphous nature of the as-prepared films whereas crystalline phases in annealed films were identified. Structural parameters such as average crystallite size, strain, and dislocation were determined for different annealing temperatures. Effect of annealing on optical constants of prepared films has been explored using UV-Vis spectrophotometer in the wavelength range of 400 nm to 1000 nm. Various optical constants were determined depending on annealing temperature. It has been noticed that the film transparency and optical bandgap Eg have been reduced whereas the absorption coefficient α and extinction coefficient k increased with increasing annealing temperature. It was found that the prepared samples obey the allowed direct transition. The reduction in optical bandgap with annealing temperature has been described by Mott and Davis model. Due to annealing dependence of the optical parameters, the investigated material could be utilized for phase change memory devices.

2

Influence of annealing temperature on the structural and optical properties of As30Te70 thin films

Abd-Elnaiem A. M., Mohamed M., Hassan R. M., Abu-Sehly A. A., Abdel-Rahim M. A, Hafiz M. M.

Materials Science Poland

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2017

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Vol. 35, No. 2

335--345

EN

Chalcogenide glasses have attracted much attention largely due to their interesting physical and chemical properties. Though few published articles exist on the As-Te system, little is known about the optical properties of eutectic or near eutectic composition of As-Te system upon heat treatment. Therefore, this paper reports the effects of annealing temperature on the structural and optical parameters of As30Te70 thin films. The bulk and thin films of 150 nm thick As30Te70 chalcogenide glasses were prepared by melt-quenching and thermal evaporation techniques, respectively. The glass transition and crystallization reactions of the bulk samples were investigated using differential scanning calorimetry (DSC). The influence of annealing temperature on the transformation of the crystal structure was studied by X-ray diffraction (XRD), while the surface morphology of the annealed samples was examined using scanning electron microscope (SEM). The optical band gap, refractive index and extinction coefficient were also calculated. The DSC scans showed that the melting temperature remains constant at 636.56 K. In addition, other characteristic temperatures such as the glass transition temperature, the onset crystallization temperature, and the crystallization peak temperature increase with increasing the heating rate. The crystalline phases for the as-prepared and annealed films consist of orthorhombic As, hexagonal Te, and monoclinic As2Te3 phases. Furthermore, the average crystallite size, strain, and dislocation density depend on the annealing temperature. The optical absorption results revealed that the investigated films have a direct transition, and their optical energy gap decreases from 1.82 eV to 1.49 eV as the annealing temperature increases up to 433 K. However, the refractive index, extinction coefficient, dielectric constant and the ratio of free carrier concentration to its effective mass, increase with increasing the annealing temperature.

3

Compositional Dependence of Hardness of Ge-Sb-Se Glass for Molded Lens Applications

Park J. K., Lee J. H., Shin S. Y., Yi J. H., Lee W. H., Park B. J., Choi J. H., Kim N. Y., Choi Y. G.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2B

1205--1208

EN

Chalcogenide glass in the ternary Ge-Sb-Se system is inherently moldable, thus being considered as a strong candidate material for use in infrared-transmitting lens applications from the viewpoint of thermal and mechanical stability. In an effort to experimentally determine compositional region suitable for the molded lens applications, we evaluate its compositional dependence of hardness. Among the constituent atoms, Ge content turns out to exert a most conspicuous correlation with hardness. This phenomenological behavior is then explained in connection with the structural evolution that Ge brings about.

4

Technologia wytwarzania i pomiary absorpcji szkieł chalkogenidkowych domieszkowanych jonami ziem rzadkich

Sójka Ł., Bereś-Pawlik E., Tang Z., Furniss D., Seddon A. B., Benson T. M., Sujecki S.

Elektronika : konstrukcje, technologie, zastosowania

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2012

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Vol. 53, nr 11

64-66

PL

Szkła chalkogenidkowe charakteryzują się niską energią fononów dlatego też są obiecującym materiałem dla realizacji światłowodów na zakres średniej podczerwieni. W pracy przedstawiono technologię wykonania szkieł chalkogenidkowych (Ge₁₆.₅ As₁₆Ga3Se₆.₅) domieszkowanych jonami ziem rzadkich (Dy³⁺, Tb³⁺, Pr³⁺). Wyniki eksperymentalne absorpcji otrzymano za pomocą spektroskopii furierowskiej w zakresie podczewieni (ang. FTIR). Podstawowe parametry domieszkowanych szkieł chalkogenidkowych takie jak: promieniste czasy życia poziomów energetycznych oraz współczynniki rozgałęzienia luminescencji beta obliczono metodą Judda- Ofelta. Na podstawie otrzymanych wyników omówiono wpływ linii bazowej na błędy metody pomiarowej. Na podstawie otrzymanych wyników zaprezentowano zastosowanie szkieł chalkogenidkowych do realizacji laserów światłowodowych na zakres średniej podczerwieni.

EN

One of the promising materials for the construction of mid-infrared fiber lasers is the chalcogenide glass. The chalcogenide glass has low phonon energy (below 400 cm⁻¹) when compared with standard materials used to produce fiber lasers, i.e. ZBLAN and silica glass.We present a comprehensive study of chalcogenide glass fiber lasers doped with Dy³⁺, Pr³⁺ or Tb³⁺ that operate in the mid-infrared wavelength range. A set of chalcogenide glass samples doped with different concentrations of rare earth ions was fabricated. The modeling parameters are directly extracted from FTIR absorption measurements performed on the fabricated bulk glass samples using Judd-Ofelt theory. Results show that, for all the dopants considered, an efficient mid-infrared laser action is possible if optical losses are kept at the level of 1dB/m or below.

5

Szkło dla fotoniki. Cz. 13, Rodzaje szkieł światłowodowych

Romaniuk R.

Elektronika : konstrukcje, technologie, zastosowania

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2009

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Vol. 50, nr 10

132-136

PL

Szkła, obok półprzewodników i metali są podstawowym materiałem do budowy elementów w optoelektronice i mikroelektronice. Praktyczna wiedza o szkłach rozszerza się wraz z silnym rozwojem ich zastosowań w telekomunikacji, czujnikach i budowie mikrosystemów. Wiele elementów funkcjonalnych fotoniki budowanych jest ze szkieł laserowych. Optyczne zjawiska nieliniowe indukowane w szkle pozwalają na budowę nowych mikroelementów fotonicznych zastępujących złożone rozwiązania klasycznej optyki objętościowej. Szkła gradientowe zastępują klasyczne szkła optyczne. W artykule, który jest trzynastą częścią cyklu prac o szkłach dla fotoniki. dokonano przeglądu najczęściej stosowanych rodzajów ultraniskostratnych szkieł światłowodowych, słabo domieszkowanych przeznaczonych dla celów transmisyjnych. Nieco odmienne szkła światłowodowe, i one są głównym przedmiotem rozważań w artykule, są stosowane dla celów instrumentalnych, a w tym szczególnie aktywnych, czujnikowych oraz przeznaczonych do budowy fotonicznych elementów funkcjonalnych. Omówiono następujące szkła światłowodowe: tlenkowe wieloskładnikowe lekkie i ciężkie, fluorkowe i inne halogenkowe lekkie i ciężkie, mieszane tlenkowo-halogenkowe, siarczkowe i inne tlenowcowe. Przedstawiono wprowadzanie do szkieł sztucznych - kompozytowych, fotonicznych i metaszkieł.

EN

Glasses, together with semiconductors and metals, are fundamental materials for building of components for optoelectronics and microelectronics. Practical knowledge about glasses extends considerably with strong development of their applications in telecommunications, sensors and the construction of microsystems. Many functional components of the photonics are manufactured of laser glasses. Nonlinear optical phenomena induced in glasses allow for building of new micro-components, replacing complex solutions of classical volume optics. Gradient glasses are replacing classical optical glasses. The paper, which is the thirteenth part of a cycle on glasses for photonics, is a concise review of the most frequently used kinds of ultralow loss, weakly doped optical fiber glasses for transmission. Slightly different are optical fiber glasses for instrumentation purposes, and they are subject of the paper, like active, sensor, for photonic functional components. The following optical fiber glasses are debated: oxide composite light and heavy, fluoride and other halide light and heavy, mixed oxihalide, sulfide and other chalcogenide. An introduction was presented to artificial gelasess: composite, devitrificates, photonic and metaglasses.

6

Positron trapping in chalcogenide glasses: a comparison between arsenic sulphide and selenide.

Shpotyuk O. I., Filipecki J., Kozdras A., Popescu M., Hyla M.

Archives of Materials Science

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2006

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Vol. 27, nr 4

167-175

EN

Positron annihilation lifetime measurements are performed for stoichiometric arsenic suphide. It is shown that two-state positron trapping model is valid for this glass as it has been shown previously for stoichiometric arsenic selenide. Two-component fitting parameters of LT computer program, describing positron annihilation in glassy As2S3, are close to those of glassy As2Se3. They are in good agreement with theoretically calculated distribution of nanovoid radii in these materials.

7

Dynamic behaviour of thermally-induced restoration effect in gamma-irradiated Ge23.5Sb11.8S64.7 glass.

Kozdras A., Golovchak R. Y., Górecki C., Boyko V. T., Vakiv M. M.

Archives of Materials Science

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2006

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Vol. 27, nr 4

159-165

EN

Temperature dependence of optical transmission in fundamental optical absorption edge region is studied for typical representative of stoichiometric Sb2S3-GeS2 glasses. It is shown that this temperature behavior changes after Co60 gamma-irradiation. The observed effect is associated with Ge-S into S-S covalent bonds switching accompanied by coordination defects formation processes. This radiation-induced optical effect is fully reversible and could be erased by the annealing of the samples below transition temperature.

8

A unified model of physical ageing in chalcogenide glasses.

Shpotyuk O. I., Golovchak R. Y., Kozdras A., Szymura S.

Archives of Materials Science

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2006

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Vol. 27, nr 4

143-158

EN

Physical ageing processes in As(Ge)-Se glasses are analyzed using the chains crossing model and the constraints theory. It is shown that short-term physical ageing in these materials is fully determined by elementary relaxation acts of inner Se atoms within Se chains leading to the straightening of the latter with further shrinkage of glass matrix. Long term physical ageing is associated with pure shrinkage of under-constrained glass network. Phenomenological model of physical ageing in As(Ge)-Se glasses is developed to explain its compositional behaviour. The main statements of the model are verified by differential scanning calorimetry for chalcogenide glasses of As-Se family.

9

Radiation-induced optical effects in Sb2S3GeS2 chalcogenide glasses

Shpotyuk O., Kavetskyy T., Filipecki J., Kovalskiy A., Pamukchieva V.

Prace Naukowe. Chemia / Wyższa Szkoła Pedagogiczna w Częstochowie

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2001

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Vol. 5

189--197