2024

Vol.30 No.4

Editorial Office

Review

  • Journal of the Microelectronics and Packaging Society
  • Volume 30(3); 2023
  • Article

Review

Journal of the Microelectronics and Packaging Society 2023;30(3):73-77. Published online: Nov, 9, 2023

Multi-Level FeRAM Utilizing Stacked Ferroelectric Structure

  • Seok Heon Kong, June Hyeong Kim, and Seul Ki Hong
    Seoul National University of Science and Technology, 232 Gongneung-ro, Buk-gu, Seoul 01811
Corresponding author E-mail: skhong@seoultech.ac.kr
Abstract

In this study, we developed a Multi-level FeRAM (Ferroelectrics random access memory) device utilizing different ferroelectric materials and analyzed its operation through C-V analysis using simulations. To achieve Multi-level operation, we proposed an MFM (Multi-Ferroelectric Material) structure by depositing two different ferroelectric materials with distinct properties horizontally on the same bottom electrode and subsequently adding a gate electrode on top. By analyzing C-V peaks based on the polarization phenomenon occurring under different voltage conditions for the two materials, we confirmed the feasibility of achieving Multi-level operation, where either one or both of the materials can be polarized. Furthermore, we validated the process for implementing the proposed structure using semiconductor fabrication through process simulations. These results signify the significance of the new structure as it allows storing multiple states in a single memory cell, thereby greatly enhancing memory integration.

Keywords Ferroelectric, FeRAM, Multi-level, Memory, Polarization

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