Glass transition temperature dependence on heating rate and on ageing for amorphous selenium films

Larmagnac, J.P.; Grenet, J.; Michon, P.

doi:10.1016/0022-3093(81)90184-8

Cited by 90 publications

(26 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The activation energy E, is determined using the theory of glass transition kinetics and structural relaxation as developed by Moynihan and other workers, [10][11][12] from the heating rate dependence of the glass transition temperature. The commonly used approach to evaluate the activation energy of glass transition is the Moynihan's method 13 and the equation is given by (1) where, β is the heating rate, and R is the universal gas constant.…”

Section: Different Methods To Evaluate Activation Energy E Using T Gmentioning

confidence: 99%

STUDY OF GLASS TRANSITION KINETICS FOR Co₆₆Si₁₂B₁₆Fe₄Mo₂ METALLIC GLASS

Patel

Pratap

2013

Int. J. Mod. Phys. Conf. Ser.

View full text Add to dashboard Cite

Metallic glasses have received considerable attention in comparison to normal metallic materials due to their superior physical, mechanical, electrical and magnetic properties. Understanding the glass transition kinetics of metallic alloys is of great importance in order to know its thermal stability. In the present paper, kinetics of glass transition of metallic glass Co 66 Si 12 B 16 Fe 4 Mo 2 is studied using thermal analysis technique, i.e. differential scanning calorimetry (DSC), by nonisothermal heating of the sample at four different heating rates. The activation energy (E) of the glass transition region is determined by two most frequently used methods, namely, Moynihan's method and Kissinger's equation. The fragility index, m is also calculated using T g , which is a measure of glass forming ability of the given system. The results show that the fragility index 'm' of the given system falls below 16. This clearly indicates that the given system is strong liquid with excellent glass forming ability (GFA).

show abstract

Section: Different Methods To Evaluate Activation Energy E Using T Gmentioning

confidence: 99%

STUDY OF GLASS TRANSITION KINETICS FOR Co₆₆Si₁₂B₁₆Fe₄Mo₂ METALLIC GLASS

Patel

Pratap

2013

Int. J. Mod. Phys. Conf. Ser.

View full text Add to dashboard Cite

show abstract

“…Then, following Tool [7], it is usual to separate the temperature dependenceflT) and the structural variation g(a) (cooperative effects). In this model, used in many previous works [ 1 ], the relaxation time can be given by:…”

Section: Theoretical Developmentmentioning

confidence: 99%

“…In order to describe the physical dependence of the relaxation rate on both temperature and structure (i.e. the departure from equilibrium), the relaxation time "~ is assumed to take a simple form, used previously by most authors [ 1 ],…”

Section: Introductionmentioning

confidence: 99%

Electrical simulation of Thermally Stimulated Depolarization Current Experiments

Bayard

Grenet

Cabot

et al. 1997

Journal of Thermal Analysis

Self Cite

View full text Add to dashboard Cite

In this paper we present an electrical model of simulation. This model is used to simulate Thermally Stimulated Depolarization Current measurements. The time constant of the model shows the same temperature behaviour as that observed for amorphous materials. The computations by means of SPICE software give results which are very close to be behaviour laws used in the theory of relaxation in amorphous materials.

show abstract

“…Thin selenium films also found a booming way in the fabrication of other solid-state devices such as Schottky diodes, solar cells and photovoltaic junctions (Ito et al, 1982;Touihri et al, 1997;Bernede et al, 1998;Lakshmi, 2001;Mukolu, 2004;Iyayi & Oberafo, 2005;Joshi & Lokhande, 2006;El-Nahass et al, 2006). Undoped a-Se is a typical p-type semiconducting chalcogenide glassy material with a high dc dark electrical resistivity (10 Ω cm at 300 K) (Mott & Davis, 1979;Kolobov, 1996;Abdul-Gader et al, 1998;El-Zawawi & Abd-Alla, 1999); however, its glass-transformation temperature T is low (below 50 , depending on its definition and experimental procedure used to define it (Grenet et al, 1980;Larmagnac et al, 1981;Kasap & Juhasz, 1986;Kasap et al, 1990;Pejova & Grozdanov, 2001;Tonchev & Kasap, 2002)). Thus, it is only possible to exploit inherent physical properties of as-deposited undoped a-Se films at low ambient temperatures, after ageing them in dark and humidity-free environment to reach structural relaxation.…”

Section: Introductionmentioning

confidence: 99%

Determination of Optical Properties of Undoped Amorphous Selenium (a-Se) Films by Dielectric Modeling of Their Normal-Incidence Transmittance Spectra

Saleh¹,

Jafar²,

Bulos³

et al. 2014

APR

View full text Add to dashboard Cite

Normal-incidence specular transmittance of undoped amorphous selenium (a-Se) films of several thicknesses ( 0.25 1 μm ) thermally evaporated on thick microscopic glass-slide substrates upheld at temperatures near 30 (below glass transition temperature of undoped Se) has been measured at room temperature in the spectral wavelength range 300 1100 nm. Above a threshold wavelength (~ 600 nm), their as-measured curves display transmittance values near that of glass substrates and exhibit well-resolved interference-fringe maxima and minima, signifying good uniformity of fabricated a-Se films. Below , the curves decline progressively to zero transmittance, preceded by a tailing-like trend of possible structural disorder origin. The spectral dependencies of optical constants and of the studied a-Se films on were retrieved from iterative curve-fitting of their -data to theoretical -formulations of an air-supported {thin film/thick substrate}-stack using the O'Leary-Johnson-Lim (OJL) interband-transition dielectric model, combined with a dielectric constant , representing the dielectric background at very high photon energies (at spectral wavelengths much smaller than measured). Regardless of the number of observed interference fringes, reliable simulation to the as-measured normal-incidence -spectra has been achieved, but were remarkably curve-fitted if we presume that a thin roughness layer ( 5 nm) of selenium was formed on top of the fabricated undoped a-Se films. The retrieved spectra display a broad peak around ≅ 0.52 μm, below which was found to vary with wavelength in accordance with a Sellmeier-like (Wemple-DiDominco) single-oscillator (normal) dispersion formula, with a static index of refraction 0 ≅ 2.42, where is the static dielectric constant of the material at zero photon energy , and an oscillator "average" bandgap energy of ≅ 3.93 eV ≅ 2 , the optical (Tauc) bandgap energy. The values of of studied undoped a-Se films deduced from Tauc-like plots were around 1.92 eV ( 0.02 eV) and the retrieved values of OJL band-tailing energy parameter (Urbach-tail parameter Γ ) was found to be in the range 40 50 meV, slightly dependent on film thickness.

show abstract

Glass transition temperature dependence on heating rate and on ageing for amorphous selenium films

Cited by 90 publications

References 12 publications

STUDY OF GLASS TRANSITION KINETICS FOR Co₆₆Si₁₂B₁₆Fe₄Mo₂ METALLIC GLASS

STUDY OF GLASS TRANSITION KINETICS FOR Co₆₆Si₁₂B₁₆Fe₄Mo₂ METALLIC GLASS

Electrical simulation of Thermally Stimulated Depolarization Current Experiments

Determination of Optical Properties of Undoped Amorphous Selenium (a-Se) Films by Dielectric Modeling of Their Normal-Incidence Transmittance Spectra

Contact Info

Product

Resources

About

Glass transition temperature dependence on heating rate and on ageing for amorphous selenium films

Cited by 90 publications

References 12 publications

STUDY OF GLASS TRANSITION KINETICS FOR Co66Si12B16Fe4Mo2 METALLIC GLASS

STUDY OF GLASS TRANSITION KINETICS FOR Co66Si12B16Fe4Mo2 METALLIC GLASS

Electrical simulation of Thermally Stimulated Depolarization Current Experiments

Determination of Optical Properties of Undoped Amorphous Selenium (a-Se) Films by Dielectric Modeling of Their Normal-Incidence Transmittance Spectra

Contact Info

Product

Resources

About

STUDY OF GLASS TRANSITION KINETICS FOR Co₆₆Si₁₂B₁₆Fe₄Mo₂ METALLIC GLASS

STUDY OF GLASS TRANSITION KINETICS FOR Co₆₆Si₁₂B₁₆Fe₄Mo₂ METALLIC GLASS