Phase-change memory electro-thermal analysis and engineering thanks to enhanced thermal confinement

Anna Lisa Serra (1) , Gauthier Lefevre (2) , Olga Cueto (1) , Guillaume Bourgeois (1) , Marie Claire Cyrille (1) , Gabriele Navarro (1) , Etienne Nowak (1)

1 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
2 LTM - Laboratoire des technologies de la microélectronique

In this paper we compare the performances of SiN with respect to an optimized SiC encapsulation in Wall based Phase-Change Memory (PCM) integrating a Ge-rich Ge-Sb-Te alloy (GGST) suitable for high temperature stability in automotive applications. Thanks to the electrical characterization of 4kb arrays, 3D electro-thermal simulations and TEM analyses performed on programmed devices, we demonstrate the higher programming efficiency in SiC-based PCM devices, thanks to the lower thermal conductivity of the optimized encapsulation. Indeed, the uniform temperature profile achieved in the active layer of SiC encapsulated PCM leads to a retention of one hour at 250°C. A theoretical model is here proposed to describe the electro-thermal behavior of the device, linking the electrical properties, such as the resistance as a function of current characteristics, to the thermal conductivity of the materials that constitute the device. Finally, thanks to our findings, we provide some guidelines to achieve drastic current reduction via the thermal engineering of the next generation PCM technology.

Mots clés: Phase-Change Memory (PCM); thermal confinement; encapsulation layer; thermal conductivity; electro-thermal simulations

Domaines: Sciences de l'ingénieur [physics]

Anna Lisa Serra, Gauthier Lefevre, Olga Cueto, Guillaume Bourgeois, Marie Claire Cyrille, et al.. Phase-change memory electro-thermal analysis and engineering thanks to enhanced thermal confinement. Solid-State Electronics, 2021, 186, pp.108111. ⟨10.1016/j.sse.2021.108111⟩. ⟨cea-03331479⟩