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Calorimetric measurements of structural relaxation and glass transition temperatures in sputtered films of amorphous Te alloys used for phase change recording

Published online by Cambridge University Press:  03 March 2011

J.A. Kalb*
Affiliation:
I. Physikalisches Institut der Rheinisch-Westfälischen Technischen Hochschule (RWTH) Aachen, 52056 Aachen, Germany; Division of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138; and Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
M. Wuttig
Affiliation:
I. Physikalisches Institut der Rheinisch-Westfälischen Technischen Hochschule (RWTH) Aachen, 52056 Aachen, Germany
F. Spaepen*
Affiliation:
Division of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138
*
a)Address all correspondence to this author. e-mail: art.tg@kalb.eu
b)This author was Chair of the JMR Advisory Review Board during the review and decision stage.
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Abstract

Sputtered amorphous Ge4Sb1Te5, Ge1Sb2Te4, Ge2Sb2Te5, and Ag0.055In0.065Sb0.59Te0.29 thin films were studied by differential scanning calorimetry. Upon continuous heating, heat release due to structural relaxation of the amorphous phase between 0.5 and 1.0 kJ/mol was observed. This value depends on the thermal history of the sample. Preannealing of the amorphous phase revealed the glass transition temperature Tg within 10 K of the crystallization temperature upon continuous heating at 40 K/min.

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Articles
Copyright
Copyright © Materials Research Society 2007

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