Multilevel Data Storage Characteristics of Phase Change Memory Cell with Doublelayer Chalcogenide Films (Ge_2Sb_2Te_5 and Sb_2Te_3)

摘要

Phase change memory (PCM) cells with monolayer chalcogenide film (Ge_2Sb_2Te_5 or Sb_2Te_3) and doublelayer chalcogenide films (Ge_2Sb_2Te_5 and Sb_2Te_3) were successfully fabricated. The PCM cell with doublelayer structure like W/Ge_2Sb_2Te_5(30 nm)/Sb_2Te_3(60 nm)/TiN/Al shows superior performances to monolayer ones, which is mostly referred to the reduction of set voltage value and reset voltage value, and the ability of multilevel data storage. Theoretical simulations of the temperature distribution of the PCM cell with the doublelayer structure were also investigated.