Finite element electro-thermal modelling of nanocrystalline phase change elements using mesh-based crystallinity approach

Author

Trombetta, M. ; Williams, Nicholas E. ; Fischer, Shannon ; Gokirmak, Ali ; Silva, Hugo

Author_Institution

Dept. of Electr. & Comput. Eng., Univ. of Connecticut, Storrs, CT, USA

Volume

50

Issue

2

fYear

2014

fDate

January 16 2014

Firstpage

100

Lastpage

101

Abstract

Phase change memory cells composed of nanocrystalline Ge₂Sb₂Te₅ with a heater diameter of 10 nm and Ge₂Sb₂Te₅ thickness of 100 nm are studied by using two-dimensional finite element simulations with COMSOL Multiphysics. The nanocrystalline Ge₂Sb₂Te₅ is emulated by using a mesh-based model incorporating crystalline grains of random size and location embedded in the amorphous media. The material parameters are modelled with temperature dependency from 300 to 1000 K, including electrical resistivity, thermal conductivity, electric field breakdown and Seebeck coefficient. This model is shown to capture the cycle-to-cycle and device-to-device variability in phase change memory cells.

Keywords

Seebeck effect; antimony compounds; chalcogenide glasses; electric breakdown; electrical resistivity; germanium compounds; mesh generation; nanostructured materials; phase change materials; phase change memories; thermal conductivity; COMSOL multiphysics; Ge₂Sb₂Te₅; Seebeck coefficient; amorphous media; crystalline grains; cycle-to-cycle variability; device-to-device variability; electric field breakdown; electrical resistivity; finite element electrothermal modelling; material parameters; mesh-based crystallinity approach; nanocrystalline phase change elements; phase change memory cells; random size; size 10 nm; size 100 nm; temperature 300 K to 1000 K; thermal conductivity; two-dimensional finite element simulations;

fLanguage

English

Journal_Title

Electronics Letters

Publisher

iet

ISSN

0013-5194

Type

jour

DOI

10.1049/el.2013.2253

Filename

6729332