Stress Buildup Upon Crystallization of GeTe Thin Films: Curvature Measurements and Modelling

Phase change materials are attractive materials for non-volatile memories because of their ability to switch reversibly between an amorphous and a crystal phase. The volume change upon crystallization induces mechanical stress that needs to be understood and controlled. In this work, we monitor stre...

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Bibliographic Details
Main Authors: Rajkiran Tholapi, Manon Gallard, Nelly Burle, Christophe Guichet, Stephanie Escoubas, Magali Putero, Cristian Mocuta, Marie-Ingrid Richard, Rebecca Chahine, Chiara Sabbione, Mathieu Bernard, Leila Fellouh, Pierre Noé, Olivier Thomas
Format: Article
Language:English
Published: MDPI AG 2020-06-01
Series:Nanomaterials
Subjects:
Online Access:https://www.mdpi.com/2079-4991/10/6/1247
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Summary:Phase change materials are attractive materials for non-volatile memories because of their ability to switch reversibly between an amorphous and a crystal phase. The volume change upon crystallization induces mechanical stress that needs to be understood and controlled. In this work, we monitor stress evolution during crystallization in thin GeTe films capped with SiO<i><sub>x</sub></i>, using optical curvature measurements. A 150 MPa tensile stress buildup is measured when the 100 nm thick film crystallizes. Stress evolution is a result of viscosity increase with time and a tentative model is proposed that renders qualitatively the observed features.
ISSN:2079-4991