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arXiv · 2001.08100

Chemical segregation in Ge2Sb2Te5 thin films during in-situ heating

Shalini Tripathi·Paul Kotula·Manish Singh·Chanchal Ghosh·Gokhan Bakan·Helena Silva·Barry Carter
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Abstract

Germanium antimony telluride has been the most used and studied phase-change material for electronic memory due to its suitable crystallization temperature, amorphous to crystalline resistance contrast, and stability of the amorphous phase. In this work, the segregation of Ge in a Ge2Sb2Te5 film of 30 nm thickness during heating inside the transmission electron microscope was observed and characterized. The Ge2Sb2Te5 film was deposited using sputtering on a Protochips Fusion holder and left uncapped in atmosphere for about four months. Oxygen incorporated within the film played a significant role in the chemical segregation observed which resulted in amorphous Ge-O grain boundaries and Sb and Te rich crystalline domains. Such composition changes can occur when the phase-change material interfaces insulating oxide layers in an integrated device and would significantly impact its electrical and thermal properties.

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Shalini Tripathi, Paul Kotula, Manish Singh, Chanchal Ghosh, Gokhan Bakan, Helena Silva, Barry Carter. 2020-01-22. Chemical segregation in Ge2Sb2Te5 thin films during in-situ heating. https://arxiv.org/abs/2001.08100

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