Innovative Multilayer OTS Selectors for Performance Tuning and Improved Reliability

C. Laguna (1) , N. Castellani (2) , M. Bernard (1) , N. Rochat (2) , D. Rouchon (2) , C. Sabbione (2) , J. Garrione (2) , E. Nolot (1) , G. Bourgeois (1) , M.-C. Cyrille (2) , L. Militaru (3) , A. Souifi (3) , Gabriele Navarro (1) , E. Nowak (2)

1 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
2 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
3 INL - Institut des Nanotechnologies de Lyon

In this paper, we investigate an innovative Ovonic Threshold Switching Selector (OTS) based on Multilayer structure (ML). Thanks to physico-chemical analysis and electrical characterization we show how MLs properties and structure can be tuned thanks to the engineering of each individual layer stoichiometry, thickness and interfaces. Ge/N-doped SbSe-based MLs OTS are analyzed by FTIR and Raman spectroscopy revealing the structural features present in the as-deposited materials and the strong interaction among individual layers at interfaces. We demonstrate the improved variability control of electrical parameters wrt standard OTS achieved by co-sputtering technique, and the high endurance capability of MLs OTS up to more than 2·10$^9$ cycles with stable nA leakage current. Moreover, we show how Ge-N bonds play a huge role on OTS thermal stability at 400° C and how they can be tuned more easily in ML OTS. These developments pave the way towards a new class of OTS materials and their engineering, ensuring high temperature stability and best tuning of electrical performances.

Domaines: Sciences de l'ingénieur [physics]

C. Laguna, N. Castellani, M. Bernard, N. Rochat, D. Rouchon, et al.. Innovative Multilayer OTS Selectors for Performance Tuning and Improved Reliability. IMW 2020 - 2020 IEEE International Memory Workshop, May 2020, Dresde, Germany. pp.1-4, ⟨10.1109/IMW48823.2020.9108130⟩. ⟨cea-02930899⟩