Daniel Franta, Martin Hrdlička, David Nečas, Miloslav Frumar, Ivan Ohlídal, Martin Pavlišta
Optical characterization of phase changing Ge2Sb2Te5 chalcogenide films
Physica Status Solidi C 5 (2008) 1324–1327
The variable angle spectroscopic ellipsometry and spectroscopic reflectometry is used for the optical characterization of the as-deposited and annealed Ge2Sb2Te5 (GST) films. The dispersion model of the GST films is based on the parameterization of the density of electronic states. As a consequence of annealing, roughness of the upper boundaries of the GST films originates. This annealing also causes the evident redistribution of the density of electronic states from the higher energies to lower energies. The roughening and redistribution of the electrons are explained by means of the phase change of the GST films from amorphous to polycrystalline structure. This phase change is accompanied by changing the conductivity of the films that was proved by introducing the terms of the free carriers in the dispersion model of the GST films.
You can also contact one of the authors: franta@physics.muni.cz, yeti@physics.muni.cz, ohlidal@physics.muni.cz
Citing Articles
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Optical properties and phase change transition in Ge(2)Sb(2)Te(5) flash evaporated thin films studied by temperature dependent spectroscopic ellipsometry,
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Modeling of dielectric response of GexSbyTez (GST) materials,
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Cited Articles
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Franta D., Buršíková V., Ohlídal I., Sťahel P., Ohlídal M., Nečas D.,
Correlation of thermal stability of the mechanical and optical properties of diamond-like carbon films,
Diamond and Related Materials 16 (2007) 1331–1335 -
Franta D., Ohlídal I.,
Influence of lateral dimensions of the irregularities on the optical quantities of rough surfaces,
Journal of Optics A: Pure and Applied Optics 8 (2006) 763–774 -
Franta D., Buršíková V., Ohlídal I., Zajíčková L., Sťahel P.,
Thermal stability of the optical properties of plasma deposited diamond-like carbon thin films,
Diamond and Related Materials 14 (2005) 1795–1798 -
Franta D., Ohlídal I.,
Comparison of effective medium approximation and Rayleigh–Rice theory concerning ellipsometric characterization of rough surfaces,
Optics Communications 248 (2005) 459–467 -
Franta D., Ohlídal I., Buršíková V., Zajíčková L.,
Optical properties of diamond-like carbon films containing SiOx studied by the combined method of spectroscopic ellipsometry and spectroscopic reflectometry,
Thin Solid Films 455–456 (2004) 393–398 -
Franta D., Ohlídal I., Frumar M., Jedelský J.,
Expression of the optical constants of chalcogenide thin films using the new parameterization dispersion model,
Applied Surface Science 212–213 (2003) 116–121 -
Franta D., Zajíčková L., Buršíková V., Ohlídal I.,
New dispersion model of the optical constants of the DLC films,
Acta Physica Slovaca 53 (2003) 373–384 -
Franta D., Ohlídal I., Buršíková V., Zajíčková L.,
Optical properties of diamond-like carbon films containing SiOx,
Diamond and Related Materials 12 (2003) 1532–1538 -
Franta D., Ohlídal I.,
Ellipsometric parameters and reflectances of thin films with slightly rough boundaries,
Journal of Modern Optics 45 (1998) 903–934