Work

Multistate resistance in TaN/(Hf,Zr)O2/Ta ferroelectric tunnel junctions

Year: 2025

Type: article

Abstract: Ferroelectric tunnel junctions (FTJs) utilizing hafnium zirconium oxide (HZO) have emerged as promising non-volatile memory elements for microelectronics, compatible with back end of line (BEOL) complementary–metal–oxide semiconductor fabrication. This study investigates asymmetric electrode TaN/HZO/Ta devices with a 6 nm thick HZO layer as FTJs for multistate resistive memory applications. The individual FTJs exhibit a resistance ratio exceeding 10× when utilized as a binary state device, with pulsing between −1.7 and +1.4 V to set the high resistance state (HRS) and low resistance state (LRS), respectively. Following with reduced write voltage pulses allows the ferroelectric device to operate with a selection of over 32 distinct resistance states (25 bits) between the LRS and HRS. This work then explores the stability of the resistance states during write/read pulse cycling, along with the stability of the state after multiple read pulses. Accessing the multibit state shows stability within 50 reads with the binary state remaining stable for more than 4000 reads pulses. With their multistate tunability and versatility, FTJs hold promise as BEOL memory elements for compute-in-memory (CiM) arrays, binary digital memory, or weighted vector matrix multiplication applications with low power consumption during computations.

Source: Journal of Applied Physics

DOI: 10.1063/5.0256686

Authors: M. David Henry, David Stoltzfus, Megan K. Lenox, Samantha T. Jaszewski, Travis Young, Jon F. Ihlefeld

Institutions: Sandia National Laboratories, University of Virginia

Language: English

Topic: Ferroelectric and Negative Capacitance Devices

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,500

Funders: Laboratory Directed Research and Development, Sandia National Laboratories