Estimate of the Crystallization Kinetics in Stoichiometry Compositions Films of Ge:Sb:Te

Carlos Virgilio Rivera Rodríguez, Eduardo Morales Sanchez, Jesús González Hernández, Evgen Prokhorov, Juan Muñoz Saldaña, Gerardo Trapaga Martínez

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DOI: 10.4236/jsemat.2012.21008                

Abstract

The aim of this work is to compare the isothermal crystallization kinetic in the films along GeTe-Sb2Te3 line with composition Ge2Sb2Te5, Ge1Sb2Te4 Ge1Sb4Te7 and Ge4Sb1Te5 using mainly Johnson–Mehl–Avrami-Kolmogorov (JMAK) model. Results obtained have shown different crystallization mechanism in the investigated films. In Ge2Sb2Te5 and Ge1Sb2Te4 films the analysis of the kinetic results (Avrani coefficient) showed that at the beginning of crystallization a metastable phase appeared with the Ge1Sb4Te7 composition, this is followed by the nucleation and growth of the stable fcc phase up to full crystallization. In contrast Ge4Sb1Te5 and Ge1Sb4Te7 films show diffusion control growing from small dimension grains with decreasing nucleation rate.

Keywords

Crystallization; Ge:Sb:Te; JMAK Model

Conflicts of Interest

The authors declare no conflicts of interest.

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